Keygens?

I know this sound like a total nooby question, but what the use of a keygen? Does it get you to where you can get a free game? Because I got banned (for my third time) and I was wondering.

keygens dont work for mw2, if you happend to find one, then its a virus.

Is their any other way to get back into the game?

Buy a cheap MW2 key on some online key store lol.