[Guitar Woman]

Here's a list of the roms you should download:

Final Fantasy 6 (aka FF3)
Chrono Trigger
Bezerk
Ninja Gaiden 1-3
Space Invaders
Contra
Anything involving Mario (except Mario is Missing & Mario's Time Machine)
Castlevania 1-4

You probably already have these, but if you don't, go download them right now.