hey guys, i need some help.

i just got xbox live (12 month version)
and i wireless adapter. I put in the WEP key for it, and it accepted, but for some reason it just wont connect after that.,

what do i do???

okay. ive been playing dead rising a lot lately. But now, after playing for a while, a message appears on screen.

it says "the disc is unreadable, clean your disc with a soft cloth and restart the console"

i do that, but the message shows up every time.
what do i do?