Read Bill Hunt on a file type as WRAPPER http://forums.adobe.com/thread/440037?tstart=0
What is a CODEC... a Primer http://forums.adobe.com/thread/546811?tstart=0
What CODEC is INSIDE that file? http://forums.adobe.com/thread/440037?tstart=0
For PC http://www.headbands.com/gspot/ or http://mediainfo.sourceforge.net/en
For Mac http://mediainfo.massanti.com/
Once you know what codec is inside that file... ask again, about finding that codec
Further John's question, what model of camcorder did the video come from and how did you get it into your computer?
I have no idea about the camera. The film was on a dvd and is an amateur film taken 20 years ago!
If this is a DVD-Video, then see this ARTICLE on VOB files, and Importing them, plus some limitations.
If this is a DVD-Data disc, then see the tips in this ARTICLE to see how to get the full details of the files.
The details of both the DVD and the files contained, will be very important to troubleshooting.
Good luck, and thank you for the details,