Update: I was unfortunately not aware of Shamus Young's severe criticism of Fallout 3 available here to link in the original piece and I regret that. It dovetails rather nicely with what I've written and it's much better executed than my piece. I strongly recommend anyone...
Okay, first of all, DO NOT BUY THIS GAME! Why? Here, I'll show you.
First of all, what would you expect in a Superman game? I picture a Superman game with bad guys to kill, a huge city to explore, and the evil Lex to destroy. Well, guess what Superman 64 is about? Fighting baddies? Nope, FLYING THROUGH FUCKING RINGS. Yes, you read it correctly. All you do in this game is fly through rings. The horrible controls don't help with this either. Neither do the jaw dropping glitches. I'm serious. I brought back the game to the person I bought it from, and slapped him in the ****ing face.
Please... just... please, do not, EVER, buy this game. Just... don't. Please. I warned you.