I think a lot of the answers in How do you help players not focus on the rules? are on point here as well. They talk about limiting time spent discussing and taking things offline, but perhaps the most important is establishing that your rulings stand and that as a more experienced player, and additionally as the GM, your interpretations of the rules are the ones that take primacy. Even above the books, if it comes to that, but certainly in absence of clarity or obvious error.

You can allow a bounded amount of "look it up time" if you want, but I don't really have the patience for that personally. "You can look it up when we're not in the middle of doing something and prove me wrong later if you'd like, but now's not the time" is a valid GM ruling. This process could be made faster by having the SRD up on a computer, having him perhaps print out his spells he's using for quick reference, etc.

How to handle a rules-lawyer player? is also relevant - though the context there is someone who DOES know the rules being argumentative, most of the answers apply to someone who doesn't as well. One would hope that being wrong all the time would slow your particular rules-lawyer's roll, but it sounds like it's not for whatever reason.

Go ahead and make the characters for your overwhelmed players

It's been my experience that about a third of players are far more interested in interacting with the setting (often with sword in hand) than building the character. While both are part of the game, some folks really do want to hurry to the former and find the latter boring. Those players are grateful when given the chance to play a competent character with interesting options.

And in a system as vast as Pathfinder only a heartless DM says to such a reluctant character-builder, "Make a level 3 character." So much baggage comes with that sentence! Race and racial traits, class and archetypes and favored class benefits, traits, feats, skills, equipment, spells, pets... that's a huge undertaking, slathered in jargon.

So don't say that.

First, get non-mechanical feedback from the player in the form of expectations for the character: hit things with sword, light things on fire with powers of the mind, sneak around and stab people in the back, whatever. Alternatively or in addition, ask for a fictional character as a reference: Link, Wolverine, Tyrion Lannister, Han Solo, whatever.

Second, build such a character as best you can within the system's limits.

Third, explain in person (if possible) the differences between the player's expectations or the fictional character and the actual character the player's going to play. Also explain that, after playing the character you built for a session or two, the player can make any (legal) changes he wants to make to it or make his own character from scratch.

Fourth, play the game! When you've such players, they really don't want to spend a whole session making characters and chatting about the game. They want to play the game. You owe it to them to at least get the adventure started, or else they'll feel their time was wasted.

It's not bad to make someone else's character, and it's especially not bad to make a new player's character. While a veteran role-playing game gearhead may balk, the player who wants to play now will thank you, especially if the character lives up to his previously expressed expectations.