google je kamarat:

reset ps3:
first you turn off your ps3 so it will be in standby mode. Then you go over to the back of the console and turn the main power off so you will not even see a red light. After a minute turn the main power off so you WILL see a red light. Now hold down the touch sensitive power button on the ps3 for about 10 seconds until you hear multiple beeps. After that your ps3 should be running in factory settings (non hd).

alebo

You go to Game, then to Saved Data Utility, and you find PlayStation Home (or whatever game data you want to delete), press Triangle and then choose delete.