Karate Champ among the old school games
Snk's brilliant Last Blade and Last Blade 2 are high up on my all-time favorites..then Samurai Showdown 2, Kof 98, and Garou, Mark of the Wolves...
Among the Street Fighter games, the original SF2 is my favorite....
for 3d games..Tekken 2
But my all-time favorite, because I played in 10,000 times waiting for another playable game for the system, was Naughty Dog's "Way of the Warrior" on the 3DO (no) system.....digitized fighters MK style, fatalities, music by Rob Zombie, and more hidden features/characters than you could ever find.....probably not the most technically perfect fighting game, but I loved it!