Found a resolution today. I contacted Archos Tech Support via Web - what a laugh - They told me to upgrade to the latest firmware. The firmware is listed in the form you fill out when you submit the ticket. I had the latest firmware. Must have been a canned response.
I contacted phone support TS and spoke to Scott who was well informed. He told me it seemed like an issue with the process I was using. - I use Mobile Clone DVD to transfer my collection to an avi file, then I use Windows Media Player to open the file, add it to my library, and then synch it to the AV500. This seems to work well for files that have a duration less than ~ 1 hr.
For items in my collection that exceed ~1 hr 10 minutes - I rip the file using the same program, then use the MPG4 Translator program that came with the AV500 to convert and then transfer in HD mode to the AV500. No need for Windows Media Player.
This resolved the issue, but I am faced with a long conversion process. ~1 hr for a 1 1/2 hr movie or video. Not a big problem for me as I bought the AV500 to store my music and have an occasional movie on it to watch on a trip.
As I said before, this device is not for a non-techy person. When I thought I had it cyphered, I realized I did not! Hopefully I am there now, just have to convert all my video again.
Tim