I have an earlier iPOD (toggle) I have had no problems, but now, I cannot turn it off, its frozen for all function.
My iPOD is frozen, nothing works to shut it down. Battery is full and it is unlocked.
iPod classic, old toggle
If you have not already, try using this procedure to Reset the iPod.
http://support.apple.com/kb/HT1320
This "reboots" the iPod. The iPod is not erased.