Well there is a possibility that the television may have gotten damaged but I think Wii had nothing to do with it as it is just a gaming console and its display cables come separately. It might be that your television may have encountered some problems and may need servicing. Furthermore it may be that your television experienced a problem with its display settings. Try turning all your settings back to default mode. If this does not work try consulting a mechanic or someone who repairs televisions.
Since We Got Our Wii, Our Hitachi Rear Projection Big Screen's Color Is "Off", Color Is Great With The Wii, But Regular TV Can't Be Adjusted, What Could It Be?
I just purchased a Wii and was preparing to set it up. The directions tell you to check with your t.v. Manual to determine if there may be a problem with a plasma or projection t.v. There was nothing in the manual, so I called LG and was told that the system could cause damage to the t.v. They do not recommend using any type of gaming on the projection t.v. I will look into the module that was recommended by fwagger before I return it.
I had the same problem with my Hitachi Rear Projection TV and was told by the repairman that you can't use a Wii on rear projection TV's because it burns out the convergence plugs or whatever their called. He said a module is sold for approx $25 that you plug your wii into and then the module into your set and it won't ruin it. I found this out 400+ dollars later.