PS3 Stopped playing DVD & Blu Ray Discs?

My PS3 has just stopped playing any DVD or Blu Ray discs? It still plays the games console discs, but it no longer seems to be playing the movies......whilst it does recognise them from the main menu.

Is there a simple fix that I am unaware off, or is this a warranty issue/common fault (the console was purchased when the PS3 were launched & is the higher spec 60 or 80GB model not sure which)

Thanks a million for any help you can offer