This is the iPod shuffle category, but if this is about an iPod classic, it will need to be "reformatted" for Windows, using the Restore process in iTunes. This will erase (reformat) the iPod, re-install its software, and set it to default settings.
iTunes needs to be installed on the computer.
When you initially connect the iPod to that Windows PC, iTunes should prompt you to do a Restore.
(If this is actually about an iPod shuffle, please post back.)