Instructions
Insert the disc properly. Wii discs will not operate in the console if they are inserted incorrectly. If the console is positioned on its side, the label of the Wii disc should face up. If the Wii stands upright, insert the disc with the label facing to the right. This is also true of GameCube discs.
Make sure the disc you are using is supported by the Wii. The console will not play discs from gaming consoles besides the Wii and GameCube. It also does not play DVDs, Blu-Ray discs or CDs.
Clean the disc if it appears to be dirty. Dampen a soft cloth and wipe from the inside of the disc outwards. Rubbing in a circular motion can cause scratching.
Eject the Wii disc from the console and turn the power off. Turn the power of the console back on and insert the disc again to see if it will operate.
Make sure you are using a Wii disc that is supported by your console. Wii systems made for sale in North America will only support discs that are also made for sale in North America. The label of your disc should say at the bottom that the disc is made for use in the United States, Canada and Mexico.