I have the same problem too.
I am having the same problem when I insert a dvd back-up. It comes up on the wii channel but when i click start the drive makes a bunch of noise and then I get a black screen w/ the error please insert the disc. I know the game isn't bad because it works on the SD card with no problems. Let me know if you guys come up with anything. This only happens on some of my back ups not all.
make sure your region switches are set to the right position
My region switches were set right, everything are functional. There are problem with game Call of duty World at War, it made alot of noise in the CD, like crazy. And Game House of the Dead Overkill, Wii console first realized the game then the wii console shut down and give me a black screen and message "Error 02, Please insert the disc Game House of the Dead Overkill". While My other Wii console (modded) were real perfect with these game. Any Ideas please help. Thank you in advance