I've slowly reinstalled programs and periodically verified that the DVD drive sees files, and it appears that the culprit was/is VLC video player. I recently installed VLC (latest version) and now selecting my DVD drive in File Explorer again lists no files and simply shows the message "Drag files to this folder to add them to the disc." I tried uninstalling VLC and rebooting, but it seems the damage (whatever it is) is done. I suppose my next step is to again reinstall Win 10 and start over(!); fortunately, I'm retired and have the time to waste.
I upgraded one home desktop to Win10 Home last year. Since then the DVD drive simply does not see files on the disks. I first thought the drive might simply have failed and purchased a new 24X DVD Rewriter; however, that was not the problem. I can play movies (I use VLC) but text or photos are not accessible. Those files are accessible on another PC still running Win7. Device Manager says the drive is working properly and the driver is up-to-date (although it is dated 2006). Is there some setting in Win10 I'm missing?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic