I thought ff tactics is a GBA game xDmost of the popular have been mentioned,
so heres some more,
Yes some of these are not the most manly of games, i know.
intellegent cube (looks simple, but its addicting)
star ocean 2
crash bandicoot (sp?) 2-3
r type (forgot the full name of this one)
street fighter vs capcom
if i remember rightly arc the lad
legacy of kain series (blood omen (dont know if blood omen works btw, last time i tested it didnt but why not) and soul reaver)
you know what i may need to know what games you like to make a decision, because i have more suggestions but i cant really be bothered right now.