If you device is frozen, and unable to update or restore, then place it in recovery mode - http://support.apple.com/kb/HT1808. Once in recovery mode, you can restore it from iTunes - http://support.apple.com/kb/ht1414.
iOS device is not responding or does not turn on - http://support.apple.com/kb/TS3281.
- Reset the iOS device. Nothing will be lost
Reset iOS device: Hold down the On/Off button and the Home button at the same time for at
least ten seconds, until the Apple logo appears.
- Restore from backup. See:
- Restore to factory settings/new iOS device.
If still problem, make an appointment at the Genius Bar of an Apple store since it appears you have a hardware problem.
- Also try DFU mode after try recovery mode
- If not successful and you can't fully turn the iOS device fully off, let the battery fully drain. After charging for an least an hour try the above again.
- Try on another computer
- If still not successful that usually indicates a hardware problem and an appointment at the Genius Bar of an Apple store is in order.