You
I'll deal with your issues first: you are an angry 14 year old.
Don't sweat it; everybody was, is or will be. Maturity can in fact be summed up as learning not to punch the face of someone who richly deserves it.
You have to remember that you have no control over the way other people behave; you only have control over the way you behave. And ... you behaved badly. People say "I lost my temper"; this is a euphemism that means they choose to express anger in an aggressive and non-productive way. Learn to choose to react differently; no one ever changed their mind by being yelled at - at best you can get someone to back down and resent you.
Oh, and because none of us is perfect and I have chosen to "express anger in an aggressive and non-productive way" myself (and no doubt will in the future), you need to know how to recover from that. This is easy: it's called an apology. There are 2 reasons we say sorry and both are applicable here: 1. to show that you know that you behaved badly and 2. to repair the hurt you caused other people.
Him
This guy was rude; there is no doubt about that. You haven't mentioned his age or the age of the group but if this guy was an adult then this is really bad behaviour; if there were adults there who didn't intervene then this reflects poorly on them too.
All the stuff I said about you is equally applicable to him; of course, he's not reading it.
Due to the wonderful diversity of humanity you will, from time to time, encounter people who are rude. They may be rude because they are: tired, drunk, just had their dog die, just got fired, have a splitting headache or are just obnoxious p*%^ks who didn't have enough parental discipline growing up. Notwithstanding, dealing with rude people is a skill and, like any other skill, you can learn it.
Here's a quick quiz. In response to his opening remark of "Let's get this over with, I got stuff to do.", which of the following is likely to give the best outcome:
- Ignoring it
- Beating him to death with your dice bag
- "Sorry we're keeping you, why don't you leave now?"
- "I was planning on a 3-4 hour session. What time is your other appointment and we'll see what we can do to accommodate it."
No 2 could be fun but No 4 does a lot with a great deal of economy, it:
- doesn't let the rude remark slide through unremarked
- shows that you care about his problems (both the other appointment and his rudeness)
- establishes expectations on timeframe
- establishes your authority
- enables the group as part of the solution
- shows what a nice guy you are.
Note: even if you say this you don't have to accommodate him! Polite and nice are not the same thing.
Expectations
When you sit down to play chess you know what you are going to get but when you ask someone to play football and you come ready for soccer and they come ready for gridiron; you have a problem. Ways of playing D&D range from treating it as a tactical war game to be won to using it as improv theatre and everything in between. All of these are valid and it's you job to give the players (including yourself) what they want out of the game.
Take 5 minutes next time you meet to find out what type of play each player prefers and describe your preferred style to them.
I think of agency as:
Players making informed decisions that have reasonable consequences
The D&D 5e Player's Handbook neatly encapsulates this in the "How to Play" section on page 6 and it is applicable to all RPGs that have DM/GM (some don't):
The DM describes the environment
The players describe what they want to do
The DM narrates the results of the adventurers’ actions
"I kinda got nerdy and got really into setting the scene. It was an opening narrative, so it took about 4–5 minutes for me to give all the backstory to the local area."
Cool, at what point did this lead to step 2: The players describe what they want to do? How much of it was describing the choices they could make? How much of the information was relevant to those choices? RPGs are a dialogue, not a monologue; unless the player's feel like they are involved in the storytelling then they might as well be at a book reading.
Back story is fine but if it was good it would be part of the story; the reason it is back story is that it is not enough fun to be the story. Back story may need to be there (or not) but it should emerge from the play; not be read at the players.
Scene setting is about providing just enough information that the player's can see the choices and have enough information to intelligently choose one; remembering that choosing to seek more information is always one of the choices.
For example:
It's a dark and stormy night when the captain puts you ashore in front of the imposing wall of the jungle. "This is where I left your friend; I'll be back at dawn five days hence. Don't be late!"
The beach stretches off in both directions, a narrow strip of sand bathed in moonlight. There are no obvious paths into the undergrowth. Sailors are carrying your possessions off the longboat and dropping them above the high water mark.
What do you do?
The scene is set and its now the player's turn.
Do they have enough information to make intelligent choices? No but you have handed them the initiative and they are now free to ask questions about what interests them. They might:
- Talk more to the captain
- Ask about their "friend"
- Ask what supplies they have
- Ask what the jungle/beach looks like
- Decide to troop straight off into the undergrowth (your job involves enabling idiots, too)
- Cast some long duration spells
- Cast Fly to take a look round
- Do something neither you nor I have thought of which is where the ultimate fun of DMing a RPG lies - dropping players into a situation and seeing what they do to it.
Now it is possible that some player's will not be comfortable with taking the initiative but the overwhelming likelihood is that within the group one or two will shoulder leadership roles. If so, they can start the ball rolling; I would suggest that you ask the other players "Are you happy with that?" to up their level of involvement.
In the unlikely event that no one seizes the opportunity, you can go on to enumerate what you think they can do. Some people like to pick from the menu rather than having to write it themselves first.
Disclaimer: This is a serious enough issue that in a lot of circumstances, it would be appropriate to kick this player out. I can see why that's not your first choice here, but just know that you may not find a perfect solution.
Situation
Here's what I'm getting from your question:
- Your dad used to play DND in college (presumably a while back.)
- He plays as if the ends justify the means - he doesn't expect to have to be nice to people if he's doing it for a good cause.
- He kind of has this attitude in other areas of life as well (we try not to psychoanalyze people over the Internet, but you brought it up more than once, so I'm taking your word for it that this is relevant.)
- Family dynamics are complicating the game dynamics.
Based on the above premises, I'm not going to suggest you have a big Talk About His Behavior; for one thing, you already have and it didn't work, plus you're concerned that he'll interpret that as a personal attack, and you know him best. So I'm going to suggest something a little unusual for the problem-players tag: Let the Wookiee win. By that I absolutely do not mean let him steamroll over you and the rest of your players/family and continue to make the game miserable for all of you. But I do think you need to apply a principle that's as true of RPGs as anywhere else: find what works, then do that. More specifically, I think it's worth trying to find a play style that he can be fundamentally happy with, and then seeing if you can accommodate that in a way that's still fun for everyone else.
Find the Fun
So, what does he want out of this game? I can't tell you that. You might formally ask (as I've done in this survey of player motivations), or bring it up more casually, or employ trial & error and see how he reacts (not my preferred option but may be necessary if you're not confident you can have a productive conversation about it.) Ideas to get you started:
- Blowing off steam/escaping from stress into a world where things go smoothly, your decisions matter, and you're able to exert influence over your environment
- Challenge/escaping from boredom into a world where things are exciting (not as contradictory with the last point as it sounds, though there's certainly a balance)
- Recognition - being famous, admired, greeted by cheering crowds, etc.
There are many more motivations for playing RPGs worth exploring, but I highlight these three because I have a hunch, based on the information you've given, that one or both of these things are true:
- Your dad is used to playing in a more straightforward dungeon-crawl/hack-and-slash style game, where NPCs say "Please rescue the prince and we'll give you lots of gold", and then you go beat up some monsters, rescue the prince, and receive lots of gold. Implicit in this style is that the ends do justify the means; your characters can be mercenary or rude, or even wreak havoc out of boredom, and it's all taken in stride because you're there to save the world. It's not everyone's cup of tea, but if you come from that to a style where NPCs don't know you're the heroes, have more nuanced personalities and problems, and react accordingly, it can be jarring.
- He feels, out of character, that he's made sacrifices for good causes over the years and people don't respect him or cut him enough slack for it, and is frustrated to perceive that dynamic being replicated within the game.
Specific advice
If the above rings true, I suggest doing the below:
- As GM, modify the game to be more like what your players want, possibly like I've described above: get a quest, achieve it, get the reward. Depending on people's familiarity, this may also be easier for everyone as you're getting into the game. Tynam's answer has some excellent specific techniques for tweaking the game style to meet halfway and helping him achieve his goals without running roughshod over everyone.
- Encourage everyone to make sure their characters reflect the type of game experience they want to have. (I would freely allow people to change or swap out their characters for this reason - this is no time to stubbornly prioritize continuity.) If someone wants to play a socially coarse brawler, let them, while making sure they understand that this will incur certain reactions from NPCs and will require others to take the spotlight during social scenes. If someone wants to play a friendly, gregarious type, make it clear you expect that to be borne out in their dialogue.
- Check in frequently to see how everyone - including you! - feels about the game. If people aren't happy, adjust where possible. If his behavior doesn't change, make sure you've made it clear that this is not only irritating, it's a deal-breaker for the rest of the group.
Outcomes
I see a few possible developments here:
- You discover that there's a particular style of game your dad likes, everyone else likes it too, and the day is saved. Hooray!
- Your dad likes one style, everyone else likes another. Suboptimal, but once everyone's aware of this fact, it's usually possible to compromise so everybody gets their favorite thing at least some of the time, and can tolerate the other segments for the sake of continuing the game. If this is the case and he's having fun sometimes, he might mellow out the rest of the time.
- You can't find a style he likes enough to choose not be miserable to play with, or his idea of fun is honestly totally incompatible with the rest of you.
If it's #3, you have some tough decisions to make. At this point you'll probably have to choose one of the following, depending on how you're balancing the various relationships involved:
You all placate him, doing whatever he wants for the sake of continuing the game. I really can't recommend this - "fun" activities where not everyone is actually having fun can sour people on RPGs (not to mention family activities altogether) for years to come. I mention it because it may be suggested, particularly if someone in the group is REALLY prioritizing the relationship.
"Look, you don't seem to be having a good time, and the rest of us definitely aren't - I know it's frustrating, but I think the rest of us are going to try doing this the way we want to do it, and we'll find some other way to socialize as a family."
Dropping the game entirely. It was a nice idea, and you gave it a shot, but it wasn't working out in practice as either a fun game or a good way to spend time together as a family, so it doesn't make sense to continue. Hopefully a substitute can be found - Netflix, 20 questions, whatever.
If this were just a friend or acquaintance, I'd've likely jumped straight to one of those last two, considering you'd already had a conversation about the specific issue. But you said you really want to try to make this work, so hopefully the above will help with that - and if not, you've still got options.
Best Answer
You are not a problem player
You said "I'm a problem player", but also have the self-awareness to recognize "I’m ruining everyone’s fun". This means you are not a problem player. You are a player with a problem. You are looking to improve and willing to work for it. You will be fine.
You are spending time with some friends. Everyone is trying to have fun, but only some people are. This can happen because not everyone has fun the same way.
I recommend the following steps to improve the situation.
Learn
Fun is a surprisingly well-researched topic. Different people enjoy different things, and it's important to know what you and each of your friends are looking for in an RPG. Here are a few resources to get you started.
I'm not sure there's a definite One True List to use. I recommend looking for a few more lists on your own to get a feel for what's out there.
Reflect
Now that you have some more background, think about each of the players in your group, including yourself. You may have pegged certain friends to certain roles the moment you learned about the role. Others are either a balance between two or more roles, or their motivations are a mystery to you. It's worth explicitly taking the time to grab a nice beverage and think about all this before you move on to the next step.
Talk
The other people at your table are your friends. You have a shared goal of having fun together. You should feel comfortable talking to them about it. Think of it like going out to dinner together. Some people love Thai, while others prefer Italian. Be aware of stronger restrictions; a vegan might not be able to eat anything if you go to the wrong place.
Remember that the group has two goals, in this order:
Here are some brief DOs and DON'Ts for this kind of conversation. For more advice, consider asking over at the interpersonal sister site.
Do apologize, to the group at large or to specific individuals, if you think you were being a jerk at any point. Do talk about yourself and your motivations, as well as what you find boring or tedious. Do let others talk about their points of view as well.
Don't declare things about other people, such as what play style you think they are. Let them conclude that on their own. Don't dictate how they should play, based on some stuff you read on the internet.
Finally, ask them for help. They may have suggestions of their own. Generally, I have found that open communication works best. Simply let them know you are aware of this problem in general, but rarely in the moment. If you start doing it again, they should interrupt you and let you know. Then, if someone asks you to stop, you stop doing it and thank them for helping you be a better player.