my vote is gta4 the realism destroyed this game for me. i played all the other gta's and enjoyed all of them but gta4 just wasnt what i wanted and was a chore just to beat.

I going to have disagree with you because, in my opinion, GTA 4 is the best in the series and what did it for me was the realism. If you want a game with less realism you should play Saints Row another very good game.  

well i hated San an. but vice city was the best IMO of the series i agree with you. Well the whole thing gta was known for was the absurd crap that goes on in it but now it feels like a mindless third person shooter.