But, for future reference, here's a bit of advice: You know that screen where it says...."SAVING. DO NOT TOUCH OR REMOVE MEMORY CARD IN SLOT A. PLEASE WAIT."....Yeah, that one? Well, it might help to, you know, not do the opposite of what it says, and then your data will be fine.
GC memory cards were/are a bit wierd.
i have two and both are kept in the same condition; stuck into slots A & B and almost never coming out. this is pretty much how its always been. yet last year the one in slot B suddenly lost all its data from a 'corrupted file'. i hadn't even used B in months and it got corrupted.
a lot of GC owners have had the same problem. they take perfect care of it yet they'll randomly lose thier data. which is why GC memory cards are wierd.