Hi
I think I had the same problem with mine. I have the original 60gb version from day of release and within the first year all of a sudden it stopped reading discs. I phoned the support number (available somewhere in the documentation, I don't have it to hand) and they took me through a few things to try like holding down the power button for 2+ seconds to do a hard reset but nothing worked so the person I was speaking to arranged to take it back without any questions.
I think it was a bad blu ray drive or laser possibly made worse as mine was one of the originals but there was nothing I could do other than send it back to Sony. I look after all of my stuff and there was no warning that it may be playing up it just stopped. Mine was under warranty at the time but the service was excellent from Sony. Only took a couple of days and this was close to Christmas as well and they swapped the old one for a replacement at the same time on the doorstep so no waiting for a new one to arrive. This was over a year ago though so things may have changed a bit.
If you do phone them try and have your console in front of you if possible so you can run through the things they suggest but word for word it sounds exactly the same as the problem I had as it turned on fine and you could access everything else just not discs.
Even with the problem I'd still have a PS3 any day over an ex-box and the red ring of death!
