Michael:
Thank you for your excellent post. I isolated the problem and found that by shortening about 1% of my file names to ridiculously short names that have no descriptive value (a few old ones were 170 characters long due to encryption) that I was able to make it work. I set it to UDF 1.5, I have a choice of UDF 1.5, 2.0,2.5 or IS)9660/Joliet.
Also, long file names are not a problem if the file being copied is on the C drive; the problem was triggered by burning a data DVD from data on a "J" drive that was setup by Cypherix 8.1 encryption software. I unlocked Cypherix before copying.
I never could find what Cyberlink's rules are for the number of characters in a file name or why the software would not take the initiative to shorten them the way my old Roxio 7 did in a PC running Windows XP. I find it interesting that newer technology makes things worse for me.