Restoring an Apple TV via iTunes
Connect one end of the micro-USB cable to the back of your Apple TV, and the other end to one of your computer’s USB ports.
From the Apple TV summary page in iTunes, click Restore Apple TV. This step might take some time, depending on the speed of your Internet connection.
My Apple TV got stuck at the Apple logo boot screen, and this fixed it. I think it actually took longer to copy the OS over USB than for iTunes to download it over the Internet.
