I've always thought that Warhammer (RP) was the absolute best of the best in gaming as it was more about the characters, storyline and plot-progression than it was about rolling 50 dice and hack/slashing your way to XP glory. Not that I didn't/don't enjoy D&D, because I do.. but I always thought that WHRP was the most fun I ever had.
As a non "role playing" choice, I'd say that Warbands has to be another of my all time favorite games. Good memories with that one. That and drunken beer-cap hockey. Or drunken Roborally. Or, anything plus adult malted beverages.
Or.. Oi, Dat's My Leg.. just for old times' sake. LOL.