if its just a dirty lens you can take your wii apart and clean the lens, or use one of those old ghetto cds with lens head brushes, maybe even blast it out with a can of air. If your still in warranty send it in to nintendo... if you have an original SSBB try playing it, if it has errors then you can send the wii in for free repair regardless of warranty. If you send it in make sure to clean off you system first