Actually, if you what you hear sounds like a motor rotating, the problem is likely very simple. Usually, after having it for a long time, the elastic band that connects the motor and the gear that opens the drive will stretch a bit, so when the motor rotates, the band will just slide without friction and it won’t open. You just need to open it, check the band’s tightness (It should be pretty darn tight if it’s okay) and replace it if needed. Relax, I’ve taken my drives apart a hundred times without knowing the first thing about anything. As long as you don’t sledgehammer the innards or anything like that, it’ll be fine.
You may have a problem though, some drives are made in such a way that if you don’t first open the CD holder, you won’t be able to take it apart correctly. If this is your case there is a failsafe for when the holder won’t come out: Unless it was made in mars or something, there should be a tiny-ass hole somewhere in front. Get something like a stick, a needle or anything remotely strong and somewhat long that fits in there and stick it in. Prod around with it while using a moderate amount of force (Don’t be afraid to put a little umph into it) and you’ll eventually press onto something that’ll automatically unlock the holder a bit so you can slide it open manually.
If it’s something else, just send it to someone who knows what the hell he’s doing.