I haven’t had to deal with this yet, but knowing my luck.. well, we’ll just say it’s probably a good idea to write this down.

Xbox360 – To reset to 480i.

Remove any Discs from the drive
Turn off the console
Turn on the console using the Controller
Press and Hold the Y button
Press and Hold the Right Trigger

PS3 – To reset to 480i

Remove any Discs from the drive
Turn off the console
Press and Hold the Power button on the console
Wait for a second beep

That’ll probably help someone out.