Good Morning, Louie!
I am embarrassed to admit that early this morning I found, right in my Start Menu, an app named Elan Touchpad Settings. I don't recall ever seeing it before but two clicks later the touchpad was disabled. Easy peasy.
That said, this issue must be unique to HP laptops with Elan Touchpads running under Windows 10. I tried a dozen or more suggested fixes from the internet. Several were for Dells, a few for HPs, all for Windows 10 and absolutely nothing worked. I even tried uninstalling the driver, but each time the computer rebooted, the touchpad was enabled again. My husband restrained me from taking a hammer to it!! ;-)
You were the only one suggesting the change to the registry. I hate mucking with the registry, but I was willing to try it. Found the app before I tried.
Once again, thanks for your help. In the future, I'll try to pay attention to what's actually installed on the computer and try to help myself!
Best regards,
Chris