I have the PS2 version basically because my PC could not support this game. Well yeah graphics are no the best, but hey, you have a WHOLE three-section city to interact with.
Other good stuff about the game is the NON-LINEAR gameplay, you choose what mission you wanna go to. You will eventually be down to 1 mission in order to free up some more. Also the game is not like some games that have been coming out lately, this game is actually LONG, and it'll take you time to get through it. One example is the Spider-man movie game, really nice game and almost just like the movie, but it took me about 1 day and a half to finish it.
And of course the variety of interaction, like that car? Steal it, you don't like how certain person looks, hit him!! But be careful, you can get your car stolen too, I don't know if you have experienced personally but in not-so-good neighborhoods someone can get you out of your car just like you do it to other people. Have you tried getting a hooker in your car? (I don't know if this is appropriate to say, feel free to edit it). If you want details I'll give them you.
In less words, great game and storyline, not short (I don't know why, but that's important to me) and I'm really looking forward to the next game, Grand Theft Auto: Vice City coming out in October.