Da_Tinker,
Do you know which generation iPod she has - if it is called iPod Video it is probably the fifth gen which I think is the only iPod to be called "iPod Vide" and have a 30GB hard drive:
iPod Classic - Wikipedia, the free encyclopedia
According to that page, this player only plays the following formats:
The fifth generation iPod plays video in MP4 (up to 2.5 Mbit/s) and H.264 (up to 1.5 Mbit/s, baseline profile only) formats
This player was really designed with the user purchasing downloadable movies and TV shows in mind via the iTunes store. Still, you should be able to convert to the MP4 format or H.264 format and make it work. Have you made sure that you set the file's screen resolution to match the 320X240 QVGA resolution of the iPOD? You might have to download all files through the iTunes app...