... Never heard of the peanut butter trick working, and I can't say I'd want to try.
If multiple of your discs can't be read, it has nothing to do with the discs themselves, so fiddling around with peanut butter might of been a bad idea. Your problem is definitely related to your Wii. But in order for us to help ya, we need you to detail your problem more. How old's the Wii, has it experienced problems prior to this, did you mod it, has it been damaged, etc.