Instead of windows explorer try dvddecrypter( http://www.dvddecrypter.org.uk/
).It is a very old program but I have found that it was able to copy from some scratched/old discs when windows explorer couldn't.Use the option to copy as image.
thanks very much for the suggestion. DVD Decrypter doesn't seem to recognize the DVD, so the choice to Read and create an iso file on the HDD is essentially greyed out. I can make the choice of the DVD as the source, then the HDD as the destination file, but the typical options to do something with that are all "decrypt", all greyed out, and produce nothing with clicked.
I appreciate the time you took to answer me, though!