I've played a lot of fighting games since the release of Street Fighter II on the Super Famicom (SNES). Some of the games which I've spent a lot of time on include:

King of Fighters series
Street Fighter Zero (Alpha) series
Street Fighter EX series
Tekken

Still a big fan of the 2D games, particularly the KOF series which I thought gave better gameplay then any of the other popular fighters. Looking foward to the new KOF98 game coming out soon.