Sounds like just the games. My advice is to try to sell the wii and the games outright. Odds are you'll get far more in return than your trade in credit.

Not to slam gamestop, it's a good business model, but they make a killing in trades. The trade credit they offer is far less than wholesale costs and their retail price on used is not substantially less than new. The profit margin is far greater on trade/preplayed. Most people do the trade-in program because they don't want to deal with the hassle of handling a private sale themselves.