If you have a choice between the GC & PS2 versions & you're not a complete graphics whore by all means get this
Graphics: Some of the best I've seen on Sony's platform; the only game that surpasses this is MGS3, and only marginally. The GC version still looks better, but only by a little bit; the PS2 version isn't as sharp and crisp, but that's about it.
Sound: Resident Evil games have always been known for their sound, whether from their excellent music or their horrible V.O. (I think I'm gonna go get me a Jill sandwich....), and this game is no different. The only difference is that the voices aren't actually all that bad this time. Most of the main characters sound surprisingly excellent, but a few questionable lines (Leon calls that giant bald dude with the ZZ Top beard the village's "Big Cheese" multiple times throughout the game) drag it down a bit.
Gameplay: In case if you haven't heard it already, here's the story: You play as RE2's Leon Kennedy who has given up police work and now is working as a government agent, whose main assignment is the protection of the President and his family. Sure enough, right as he starts his job, the Prez's daughter Ashley gets kidnapped by a Spanish cult. You travel to Spain, not really expecting your assignment to take too long. Sure enough, the villagers are violently insane and aren't so willing to let you take Ashley back to the States, so you must slaughter legions of them (as well as many excellent bosses) to escape. The story won't win any awards, but trust me, it gets much, MUCH better. Changing the camera view is this game's first big stray from the older RE games; instead of fixed camera angles (which often led to incredible frustration), you now have a behind-the-back view, which works amazingly well. The gunplay is violent and incredibly satisfying; blow a villager's head clean off with a shotgun shell and tell me that you didn't enjoy it. Also, you can shoot enemies where you want to, and they'll react accordingly; shoot a villager's arm, and they'll drop their weapon. Shoot a villager's knees, and he'll collapse onto the ground. It's satisfying to the tenth power, and you'll never tire of it. The action is broken up by some clever puzzles (many of which are much better than first few games' crate-pushing puzzles), although many of them are of the "find this item to fit into the slot" variety. One more of the things that's different from previous installments in the series is that you are no longer fighting zombies; you are actually fighting humans though, although their A.I. often makes you think that they are zombies. They do show intelligence sometimes by using weapons or setting up ladders to get into windows, but they tend not to impress in the brains department. Guess there aren't too many good colleges in the middle of the European woods. Anyone, one of the best things about the gameplay is the weapons upgrade system. The trusty shopkeep will not only buy things from you and sell you new weapons and health items, but he'll also upgrade you weapons, including their power and rate of fire. Not only that, but you can buy items like stocks and scopes that you can attach to your guns to improve their performance. Moving on, even after you beat the single player mode, there are still many things to do. Not only can you replay the game with different difficulty settings, but there are also unlockable side missions. There is Assignment Ada (starring Ada Wong, of course), Mercenaries (which is endlessly re-playable), and the new-for-the-PS2 Separate Ways (also starring Ms. Wong). When you do good in these bonus missions, you can unlock new weapons and costumes for the single player game, which makes you want to go back and play the main game again. If you're the kind of guy who loves a game that you can play over and over again, yet still enjoy every time, this game is heaven. If you can only buy one game for say, the rest of this console generation, this is the way to go. Overall: If you like action games, go buy this game. If you like survival horror games, go buy this game. If you liked the previous RE games, go buy this game. If you own a PS2, go buy this game. If you don't have a PS2, but have a GC, go buy the GC version (it's just as good, save for the new extras). You may be asking, are there any problems with this game? Well, the voice acting is a little goofy at times and there are some really frustrating missions and boss battles, but aside from that, the game is just about perfect. GO BUY IT NOW.