[KLUG Members] Screen resolution changed, can't get it back.

[Brock Inglehart]

Loaded Ubuntu 8.04 32 bit on my old sandbox computer with a likewise old
crt monitor and the initial screen resolution from the loading was 10??
x 768.  That fit and all was well.  I did the updates (all 111 of them)
and when I rebooted, the screen reset to 800 x 600.  That won't let me
see the entire dialog box borders of many of the settings I am trying to
change.  The whole bottom is cut off behind the bottom panel.  I can't
get to the "go/whoa/start/stop/cancel buttons.  When I go to the screen
resolution panel, it no longer shows any resolution above 800 x 600 so I
can't fix it.
How do I get the old resolution back?