Instructions
Turn on your console and allow the main menu to load. Press the "Eject" button on the front of the console to remove the disc from the tray. Return the game disc to its original case to avoid scratches.
Open "Settings" from the main menu. This is the second menu option from the far left side of the screen.
Open the "System Settings" folder.
Choose "Restore PS3 System." An on-screen prompt will load, describing what happens when the software is restored. The original firmware version that came installed on your console will be reinstalled and all data on the hard drive -- including saved games, trophies, profile information and any media files -- will be permanently deleted.
Select "Yes" to continue. Do not turn off your PlayStation 3 during this process. The console will reboot itself when the recovery is complete. You will have to input all of your setting selections and profile information again.