I reiinstalled (avoiding past missteps), to a console, and from it
installed xorg and fluxbox. I then ran xstart from console and all went
well.

With one exception. I'm in what looks like VGA mode with large crude
characters. It seems a problem (or symptom) is that installation did not
create a /etc/X11/xorg.conf.d/ directory that should holding, I
presume, a 20-nvidia.conf file. I created them by hand, but startx
failed with error in log to effect that there is no server section.
I suspect this is not the file that should have a Server section.

I purged and reinstalled xorg without luck. Installed were libglu1-mesa,
x11-apps, x11-session-utils, x11-server-utils, xinit, xorg,
xorg-docs-core.

The xorg log tells me that it is using as system configuration
directory, /usr/share/X11/xorg.c. Because this file does not exist, the
log complains about missing layout, screen and monitor definitions. It
seems xorg is using defaults.