If it is copy protection, it is the oddest I've ever encountered.
These disks all play fine in my Toshiba recorder in my living room. One will play in my Sony in the bedroom, any of the others cause it to lock up after 5-10 minutes (it will freeze one frame on the screen and not respond to any commands, must unplug it, hook it back up, and eject the disk before it loads again). They would only play with one player on my computer (though, as I mentioned, it took 30 minutes or so to load). That is why I assumed they were bad. Exchanged them and the new ones were the same.
Research before coming here (a search for that error message led me to a similar thread here), led to recommendations of numerous programs to try (already had imgburn, DVDShrink, and AShampoo). One highly recommended program ran for three hours and had ripped about fifty percent of the DVD when it tells me there's no more disc space (!!, it should be copying into 40gig of empty). I checked and found there was 36gig of files in the HD directory for this DVD! I deleted all that and looked at the DVD in explorer ...there are about 70 VOB files of over 1gig each listed, yet right-clicking the DVD drive and checking properties shows about 6gig (must be a dual layer disk).
Some more experimentation, and many more downloads, and I found a combination of software (one explicitly stating it wouldn't work with the other) that would copy these disks in about thirty minutes each. Lost a little quality as I was recording to single layer disks, but the copies will play quite well on all my equipment while the originals only play reliably on my Toshiba. From watching the extraction process it seems the data is contained in two or three of those many VOB files, which ones vary from disk to disk, with the others being ...??
If this is copy protection, it is absurdly intrusive; and unconscionable that the consumer should have to go through such an ordeal in order to use the disks in any player or computer in the house.
BTW, since "discovering" imgburn (someone sent me a bin file and I had no idea what to do with it) I use it for most of my burning; by the time Ashampoo has loaded imgburn is already burning. I like simplicity.