I just keep my Brawl in there since I don't have a HDD yet and play that a lot am using my 16GB Flash drive to play games, and surprisingly i have all the games I want to play on it including Deadly Creatures with the exception of Brawl.
When I get a hard drive in a week or two I'll replace Brawl with F-Zero GX which I also play a ton
Just have a disc in there at all times, don't insert blank discs, a gamecube game you play often is best IMO