I totally forgot about Snowboard Kids. I remember renting it when I was in middle school and staying up all night playing it! I don't remember if it was 1 or 2, but I am definately going to have to go buy them now. Hopefully, they're as good as I remember. Well, at this point about all I remember is the characters having gigantic noses.
Gamestop really is a sucky store. Most of the preowned games are in terrible shape. I think it's more of a statement about the average person who sells their games to gamestop than the store. However, ocassionally you can find preowned games still in good shape (i.e. box and manual in mint condition). I've only bought one preowned game that didn't work and I was able to exchange it w/o any issues -- I think they have a 90 day guarantee.
In Madison, WI there are several independent preowned game stores that are much better than gamestop. They seem to only buy items in good shape, they clean the items really well, and have all systems spanning all the way back to 2600. They have prices about the same as gamestop too. You should check your yellowpages for similar stores.