To clarify you need to have the iPod plugged into the power adaptor into a wall socket when you perform the reset. This performs a Hard Reset.  Doing it when its not plugged into a wall socket will not help.

More over it will not help plugged into the computer.

On the apple site it does say that if the battery is fully depleated there may not even be enough energy to tell the computer its plugged in, this might be your issue as well, again the wall adaptor is what you need.