I would try the Anapod Reinitializer (Link Below) it is a great tool that will allow you to format your ipod to a windows format, In my experience most ipods are mac formatted and thats where the troubles with windows begins. Anyways after you reformat it you can initialize it.
This tool works great when the pod can be seen in windows but not itunes. After you reinitialize the ipod it should show up in itunes.
Other things I've found that help you avoid problems:
-start up itunes before you connect your ipod
-never use the safe eject hardware to eject your ipod, always use itunes to eject
-wait until your ipod is fully disconnected before you unplug the cable
I hope this works for you let me know!