How to reformat Mac Formatted iPod on Windows
Step 1, Download the latest version of iTunes
Your first step should be to ensure that you have the very latest version of iTunes. You can do that by going to Download iTunes. Install that, and when you hook up your iPod, you should see it show up in iTunes, then when you click on the iPod on the left side of iTunes, you'll get to the summary screen.
Step2 , Click the "Restore" button and you should be prompted to choose between four different options:
Restore Option 1: Restore - Restores with same iPod Software version already on iPod.
Restore Option 2: Use Same Version - Restores with same iPod Software version already on iPod even though a newer version is available.
Restore Option 3: Use Newest Version - Restores with the latest iPod Software available.
Restore Option 4: Restore and Update - Restores with the latest iPod Software available.
If you get to this point and it rejects it, you should take your iPod to the closest Apple store (find one here: Apple Store Locator) and ask them to restore it for you.