Any idea what this is (anomaly on screen)?

No, your first instinct was correct. It's the DPI setting. I can easily reproduce this (and fix it by changing it back) on different machines by setting the DPI to 120.

 

Well, I'd say sparx has nailed this one......just not gonna happen, no matter what, with the DPI set higher than 96.

After reviewing a bunch of other s/w, I have yet to see an About window with an image at the top; most all have absolutely no images at the top and none of the windows are resizeable (they're all fixed).

Actually, I'm not sure why ESET even bothered to include that image in the About window. I mean, it's pretty and all but does an About window need to be a work of art (or even resizeable, for that matter)? It just needs to contain textual information, right?

 

Tried that, no change.

 

As far as I know, you can change the memory reservation for VGA in BIOS.
To enter the BIOS, press F2 during POST (so BEFORE Windows starts)
Change the amount of memory to test it, and don't forget to save the settings.
Don't forget to revert the setting after testing.

Greetings from Holland!