I don't exactly like any of them, I don't know why, I just mess around with the cars for a few minutes then get bored with the missions and quit, thats for GTA 3, San Andreas, Chinatown Wars and Vice city =C. I think I liked GTA 3 the most before I got bored with it though.
San Andreas -The best rampages are done here, especially with cheats. You can spawn an F-18, tank, and helicopter. The bicycles were cool. The map is massive. and it makes me laugh, it's funny. and just a half step behind it is chinatown wars. The perfect pick-up and play. Always down for doin damage.
But it's a game.So gameplay comes first.By the way GTA IV graphics is unimpressive compared to other 2008 titles like MGS4. Vice city is the best.