Can't quite decide on the order but my top 5:
Final Fight (hence my username)
Euro League (wasn't great, but played it a lot at school)
There's one other game I don't know the name of that I spent 2 summer holidays playing. Sort of like pacman but you get chased by these octupus things. By dropping fish, the baddies grow until they get get stuck between the walls and you can catch them. Anyway, if i could remember what it was, it'd make my list.