Ok when you say mess up i assume that you mean something like brick, and this wont happen no matter how many backup GC games you throw in. Bricking only occurs when people firmware update there wii which actually changes the settings/changes in the wii that you can't tamper with yourself.
The most probable outcome that the wii would respond to would be just to either accept the DVD or reject it, that simple. Hope this enlightens you a little. -sLibs
