Nevermind.  Found a utility on Nvidia's site that autodetects (via Java) what you have.  It downloaded a driver/software package that let me get the video back to where it should be.  It's technically a Win 7/8 driver, no formal 10 driver available, but it works.
I have an older Dell machine operating as my daughter's computer.  It's from 2007, but it still works.  It had Win 8.1 on it, and other than it running some things slower due to it being an older machine, it mostly worked. However, this morning, I put Windows 10 on it, and I'm having a problem.  Technically it still runs, but the video card is "unsupported".  What's funny about that is the "Get Windows 10" upgrade icon that was sitting there for two months told me there were no problems, that everything would work fine.  When I actually ran the upgrade, it said my video card might not be compatible - gee thanks, guys. So I ran the upgrade, got Win10 on there, it all WORKS, but because the video card is unknown to Windows, it defaulted to the "Basic Windows Video" option, and it looks well, not great.  I looked around a bit, pulled my service tag, and there's nothing for this machine for Windows 10.  That's not a huge surprise, mind you, but there we are. What I'm wondering is this..  Does anyone know of drivers for Win10 for this machine?  I never changed the video card from the original specs.  Running speccy tells me it's "Nvidia", but doesn't go into any details. I don't want to revert back to 8.1, I want to stay with 10, so is there a way to  a) Figure out exactly what I have?  Using my Service Tag was inconclusive.b) Force the 8.1 drivers to be used? 
Inspiron 531 & Windows 10 Video