Just a quick note. If you are experiencing problems like freezing and you can't use the System Restore function, the easiest way to fix it is by swapping your PS3 hard drive into another system and formating it.
I just remembered you'll need to have some kind of media with the PS3 Firmware on it.
Follow Sony's steps here:
I prefer using the PC Update method whenever I update my PS3 firmware.
You can use any external drive (thumbdrive, flash drive, media card, etc.) as long as it has enough room for the update. They're usually around 130mb.
Then press Start and Select at the same time on the controller and it will go through the motions.