I fixed my gamecube!!!

All I did, was followed the instructions on nintendo.com for fixing errors; I cleaned my disc the way that they say (cotton towel & a little water, in a circular fashion, from the inside out), and boom, it started working. Now, I'm not sure if that's partially because of my earlier work cleaning the lens, or just cleaning the disc properly. Whatever, I'm just glad it works.

Thanks to Sperry1989, it was your link to nintendo that led me to finding the solution.