Disc never loads

If a disk wont load that is due to one of two things, either the inside of the ps3 is dirty, or the disk is dirty or damaged..

First you could try purchasing a bottle of compressed air thats used to clean computers,

And then try spraying out the inside of the ps3 when the cd door is open.. Then purchase a lens cleaning disk, and run it a few times inside the ps3

If that doesnt work, try to get one of the scratch repair kist for cd disks, and try to clean and repair the game itself as best as possible.

Yes it sounds like the disc needs cleaning or there is some overheating going on. You should send it in for repair or fix it yourself