I have the 60gb PS3 from launch, and have yet to have any disc issues. Only noticeable problem I've had is a couple days ago I came downstairs to turn on my PS3 and noticed the red light for standby was flashing. I pressed the power button on front and nothing happened, so I switched it off and back on with the back switch and I was able to turn it on. That's the only thing it's done to me.
Since it's out of warranty, you might as well try opening it up.
But first, have you tried turning it off and then back on and giving it another go? And have you tried the software eject through the XMB? Sounds pointless but you didn't state you tried them so might as well cover all bases here.
But as far as opening it up, the only issue I can see as a problem is the BD-drive is a small form factor BD-ROM drive. Meaning, if you open the case, it's still going to be a closed disc reader. You might try and open the actual disc reader, but that's taking it a bit far and if you are not careful, you risk seriously messing up the pickup head.
There might be a manual eject hole on the disc reader itself, like normal disc drives. Though I have not found anything to state that is indeed the case on the BD-ROM drive.