I suggest you read the transcript to the Good Eats show on freezing, or, better yet, find a copy of the episode to watch. (Good Eats is an American TV show focusing on food science.) Here are some relevant excerpts:
[In the freezer,] any present bacteria are going to have a devil of a time finding the moisture they require to live, breed, survive. Since they themselves contain a considerable dose of H2O, freezing halts bacterial activity altogether, though some of the little beasties can survive to decompose another day. While it is in this frozen state, the meat will remain unspoiled for years. But there's a problem. You see, home freezers work very slowly. That means that as those little H2Os start to line up inside, they'll create huge, sharp, jagged crystals that will rise up, slicing and dicing their way through cell walls, muscle fibers, and pretty much anything else that gets in the way. Now while frozen, you won't notice this damage. But when it comes time to thaw, all of those perforated cells will start to leak out moisture all over the place. It's called drip loss and it's not a sign of good eats.
Therefore, if you are buying the meat fresh (i.e., it is not already frozen), then you need to take special care in how you freeze it:
One good way to prevent drip loss is to freeze the target food very, very quickly to a very, very low temperature. So that instead of creating huge, jagged, nasty ice crystals, you get very, very tiny little ice crystals.
The episode goes on to describe a process for freezing meats at home (basically, the idea is to use small pieces of meat, freeze them separately on a sheet tray, and then once they are frozen transfer them to a bag for long-term storage).
Even though the meat will technically be safe to eat for years, there are a few caveats. For one thing, the environment in the freezer is very dry. That can cause moisture on the surface of the meats to sublimate and form ice crystals, otherwise known as freezer burn. This can be avoided by packaging the meat in a vacuum (e.g., vacuum sealed bags), however, if you don't have a good vacuum sealer, I would suggest limiting their freezing to 6 or 8 months in order to avoid freezer burn. Another reason to make sure you use an air-tight container is that fats are very good at picking up flavors of other items you might have in the freezer.
I am fairly certain the "fats will surely go bad" claim is a myth, especially since fat alone is a good preservative. Perhaps you should ask that question on Skeptics.SE.
I like to put the meat in a largish ziplock bag and flatten it out so it occupies the whole flat area of the bag but is only a couple of cm think. Then I press a chopstick into the meat lengthways both horizontally and vertically to create indents in the meat, as if I was making a naughts and crosses (tic-tac-toe) grid.
Then I freeze it lay flat in the freezer. Then when I want to use it I can 'snap' off squares of meat (along the indentation lines) to the amount that I need and I don't need to defrost the whole pack in a single go.
To defrost (I don't have a microwave) I leave the pieces on a metal tray for a little while, turning occasionally. This usually defrosts them in an hour or so, depending on how many there are
Best Answer
Broadly this is OK.
By broadly, I mean a couple of things. First, I'm assuming you are cooking the meat very thoroughly. That both means for long enough time to be completely thorough and hitting high enough temperatures to kill the main nasties off. Second, it naturally assumes you observe good practice with regard to not letting it sit for long periods, not co-mingling uncooked and cooked meet, yada-yada-yada.
I do what you're describing lots of the time myself incidentally, and have done for years without incident.
Of course, as I'm sure you know, one thing that is certainly a really bad idea is to freeze defrosted meat without cooking it.