Topic on Emulation talk:Wii
Aside of the methods that uses a Wii+homebrew, if you want to do it from your computer you are gonna have a pretty bad time.
GC/Wii DVDs have a special logical structure, that normally confuses drives.
It seems thanks to the prosperous xbox community, important debug commands for some LG readers have been discovered, allowing to rip games. EDIT: plextor drives seem also to be okay