The top four would have to be:

1.VIII-Because of Quistis,the juctioning system and the great graphics,music and story.
2.VI-Because of Celes,Terra,Shadow,Kefka,the amazing story and music.
3.IX-Because of vivi,dagger,the great music,story and gamplay.
4.IIj-Because of Maria,the good music(for its time)and the gamplay is fun.