Street Fighter II. I don't understand why. I'm not bad at Street Fighter IV, I kick ass in Mortal Kombat and Soulcalibur, so why Street Fighter II? I don't know, but I still love it. Although, I still kinda prefer Mortal Kombat. Street Fighter is extremely good, but Mortal Kombat amuses me a lot with it's over the top deaths and characters and it's sort of old Japanese action film (by old, I meant before many of them were along the lines of "The octopus Schoolgirl Massacare 3) storyline, which isn't a very good storyline, but that's why it amuses me.
Plus, something about the idea of a ninja who throws roped spears at people while yelling in some enraged voice "Get over here!", and then proceeding to take off his mask to reveal a skull that bursts into flames and then spits fire at the enemy who then screams in agony and then explode, followed only by some man squealing "Toasty!" in a high pitched voiced I find extremely awesome.