How to Restore your iPhone or iPod to factory settings
If something happens to your iPod or iPhone and you can't remedy it with a reboot, you will need to restore your device to factory settings. This is not difficult to do and requires only your computer and your device. You should only restore your iPod to default if absolutely necessary, because you will lose all of your files and folders. Make sure you backup your music and photos before you do it! Good luck!