iMovie Clip Trouble in PowerPoint

I’ve got a problem that you or one of the PowerPage readers may be able to help me with. I have no trouble inserting short film clips created in iMovie into PowerPoint 2001 and v.X presentations on my PowerBooks, but the same .mov clips show up as audio only files instead of video when I try to insert them in PP 97 or 2000 on PC’s. I’ve installed all of the Office updates on the PC’s, as well as the latest versions of WMP and QuickTime to no avail. I can work around it by creating a Hyperlink to open the movie in a new QuickTime player window, but is there a better way to do it without having to purchase extra software to convert the clips to another media format?