For me the most fun GTA's were GTA2, VC and SA. Never got GTA4. Gameplay wise not a bad game, obviously, but it just didn't interest me. I played the story for a couple of hours and I got bored, maybe the story was too slow for me. Apart from that, you can do the same things you can in every other GTA - smash shit.. which I actually prefer in previously mentioned GTA's.