Super Street Fighter 2 will always have a place with me
It is by far my favourite of the Street Fighter series. The ones before it weren't bad, but each new one added a bit more, until after Super SF2, then it went downhill..
i also liked Samurai Showdown.. it was the first fighting game I played that included weapons that didn't completely throw off the balance..
as far as recent games, I would go for Soul Calibur 2
something about fighting with weapons is awesome *grin*