Street Fighter 2 (SNES) & Street Fighter 2' (PCE)
Dracula X (PCE SCD)
Dragon Force (Sat)
Xmen vs Street Fighter (Sat)
Virtua Fighter 2 (Sat)
I'm not naming current favorites here, just the games I've spent the most time with over the years. This doesn't mean I think they are the best games ever, just that they won my attention in times past.