If your Ipod touch has locked up and you cant get it back then you may want to force it into restore mode. This is a very easy task but beware it should only be used when all else fails because it erases all the media off of the device.
*Warning, this deletes your songs and videos but will make the Ipod work again*
Step2
Make sure your Ipod touch is connected to the computer with the usb cable when doing this.
Step3
Press the HOME button and the SLEEP/WAKE button at the same time and hold them down. The power off screen may come on but disregard it.
Step4
When the apple logo pops up on the screen release just the SLEEP/WAKE button and continue to hold the HOME button.
Step5
After several seconds the connect to itunes image will come up. You can release the button and continue.
Step6
Now start itunes. Your device should be recognized as in restore mode and you now just have to click restore. It may take a few minutes but your ipod should be back to factory condition and fully functional. GOOD LUCK.