Not reading blu ray disc

First off you will need to back up your ps3 system. To do this, first insert a USB memory stick and then go to System Settings and then Backup, then select the USB memory stick. If the backup gives an error then your have too much information on the PS3 so grab the important things such as save data from the game folder.

You can go to saved data and then go to each saved file and press triangle and select copy. If the save data is grouped in folders then you can press square to ungroup the data and then its easier to copy as you will have to do it one by one. If you have any music files or video that is not saved anywhere else then you may want to back that up too. 

After all the data is backed up then go to System Settings and select Restore PS3 System (There is also Restore Default Settings just above it but that didn't work for me.) The PS3 will ask to format the Hard Disk. This means everything will be gone (If the backup worked then you can restore it all later but if it did not then you will have to reconfigure your Playstation the way it was. Select Quick Format. The PS3 will restart after a few seconds and will start up the way it did when you first got it. After Configuring the initial setup, insert a game and check to see if it works. If it does then restore the backup if it worked or restore the game saves and other data, then set up the PS3 with your old settings. 

If the game does not work then you are going to have to call sony while beside your PS3 and tell them you tried the Restore PS3 System option, have your Receipt from purchase at hand or else you will not be able to arrange an exchange under warranty.

Good luck.