This is really the 1st gen iPod from 2001, with a non-touch non-click wheel that physically turns, and connects with a FireWire cable?
Make sure the Hold switch is not in the ON position?
The older iPods did a reset differently from more recent iPod that have a click wheel. Be sure you are following the appropriate reset steps in this document, based on the actual iPod model.
If it's a 1st gen iPod, it would be How to reset iPod, iPod (scroll wheel), iPod (touch wheel), and iPod (dock connector). The buttons to press and hold are different from later iPods.