So I moved on to another distro, called Manjaro, which is currently installing from a USB (I continued to be able to boot from USB under the weird, not specified BIOS option to do so). On install, I was not presented with an offer to save Mint though I was able to save Windows. I will advise if this turns out to be useful.
I did it and, IMHO as par for the course with Linux, there was no failure to disappoint along the minimal amount of good.
The difficulty is that when I clicked the "install" tab, I was confronted with an error message stating I was not on line and that installation was not possible without it. Not too bad as I had a wifi dongle in place. I was reasonably quickly able to use the network controls to find my network, get it going and proceed to full install. This wiped out Mint, as I was given no option to use any partition other than the existing Mint partition for the permanent Manjaro installation.
I went away from the install for a few minutes not wanting to babysit it, and lo and behold, it installed well and asked for a reboot, which I performed. When it came back, I found Grub waiting for me, allowing me to choose between Manjaro and Windows -- the exact thing that Linux Mint could not do for me.
Alas, that was where the good news ended. The fully installed version of Manjaro not only did not recognize my dongle as its temporarily installed version had, it did not seem to have software to recognize wifi under any set of circumstances. No network control menu option showed me the available wifi networks; indeed no menu option was available to allow me to find or fiddle with a wifi adapter much less to connect to a network. I booted and rebooted; I pulled and replace the dongle; no recognition either way. I may try again with a different wifi dongle, but until then, I have no internet on the Linux OS other than to connect with a relay device that I share with my son that receives wifi but delivers it to a computer via ethernet wiring. (He uses it for his gaming console so my time with it is limited at best.)
So for all the effort, I am in the exact same situation I was on Christmas Day 2019 when I tried to upgrade from Linux Mint 2017 to 2019, an attempt that ended in total failure after many days' trials and tribulations and left me with no backup for Windows for about 5 years. But Manjaro is a lesser product than Linux Mint 2017 despite 8 years having passed, so I am in some ways worse off than before, though I should be able to recover my data if Windows goes down for the count.
A final cautionary tale: Manjaro also cannot play videos that Windows 7 from about 2010 can on that computer. I tried loading a video file and it played for about 3 or 4 seconds before my computer schizzed out with diagonal lines, effectively BSOD. I had to perform a hot reboot and I presumably would have lost work if something else was going when the machine crashed.
Ultimately Linux seems to suffice if you don't make a lot of demands on it and don't expect too much and if you don't mind a steep learning curve to attain a barely acceptable emergency solution for something like data retrieval in a crisis, especially if you are the guy who uses a computer as a mere tool for something other than being in the computing industry.
