Aside from Beach Spikers,Super Monkey,and the Sonic games. I ask because I'm planning to make my girlfriend dream come true by buying her a GameCube(she want one but cannot to afford to invest too much into videogames).
I'll second this one, although the only female I've played it with didn't seem to want to invest time into not sucking. But, if it would be for her own GameCube, she could get good at it, so it's a good pick.
Mario Golf is another one, if she happens to like golf.
Look around and see if you can find the Mario Kart bundle. You might get lucky if you go to a store that's a bit out of the way. It's certainly a possibility; I was seeing the Zelda bundle last year a few months after Christmas at select places. Great deal.
And if you can't find it, I recommend MKDD anyways.
No, not true. My wife likes it, but she doesn't have any desire to actually play it, just watch me. And I know others that don't want to watch or play. They get scared too easily.