good luck if you can find it in a used store, though.. i haven't seen it in a while, but make it a duty (or what have you) to pick it up. usually ~$5. i've logged waaay too many hours in it. <3
the third GBA castlevania game (don't remember the name of it)
Golden Sun & the sequel
Pokemon
Chu Chu Rocket (if you can find it, much harder i'm assuming)
WarioWare/twisted
Kirby & the Amazing Mirror
Mario & Luigi SuperStar Saga
remakes:
yoshi's island
link to the past
donkey kong country
no.
avoid the second one like the plague.
the other two are vastly superior, and will more than compensate for not owning the second.
trust me on this.
i totally forgot about metroid and fire emblem, though.. blah. /i'd recommend them, too
M&L:SS wasn't bad. No one has mentioned Advance Wars... those were fun games. Of course there's always Pokemon games, too. I liked Sonic Advance... you could probably find that pretty cheap.