Wii will not read discs, any ideas?

I remember seeing a thread about this before, but I must not know how to navigate fluther’s search engine correctly or something.

Anyways, the wii will turn on and you can play games that don’t need discs and what not, but as soon as you put a disc in it makes a sound like it’s trying hard to read it, but then doesn’t. It then says the disc is unreadable and the wii needs to be reset.

I’ve heard this is a common problem, but is there a way to fix it? My brother (the wii’s owner) was just thinking about buying another, but I’m sure there’s probably a cheaper way of going about it.