The original iPod model was only 5GB and 10GB (and it had a scroll wheel that actually turned in a circle), so unless someone opened it up and upgrade the hard drive, that is probably a 2nd gen iPod (or later). This document has all the iPod models
There are DIY guides
If you do a Google search on something like "ipod repair" with your city name, you can probably find an repair business that will do repairs. It nice and big, and fairly easy to work on, if you are good at such things.