If you have tried several games and all the CD's won't spin it's one of two things.

1) The Lens is dirty so it doesnt think that there is a Cd in there in which case cleaning it will do the trick

2) The motor which spins the CD has gone in which case you might as well chuck it in the bin and buy another second hand one.

I'll sell you mine if you give £20 to a charity of my choice plus you pay me for postage.