I did Adept update on Kubuntu 7.10 tonight -- rebooted -- desktop is blank!

[roger at rogerchrisman.com]

Desktop went blank on my other Kubuntu 7.10 computer after routine
Adept update tonight. After reboot it now has no desktop icons, no
task bar, no context menu. Nothing but a blue desktop image and a
white cursor arrow. Rebooting again doesn't fix it. Same for both
original user desktop and the additional user's desktop I have on that
computer.

What happened?

_What I did
Tonight I did a routine update on that computer (a six year old AMD
Athlon i386 ATX with 1G ram and Kubuntu 7.10) via Adept. I didn't look
at what was updated, just updated everything that was available. It
had been a couple weeks since the last update. Everything seemed to
update fine. So I quite Adept and rebooted.

_Problem
Now when I boot up that computer and log into either user (I have 2 on
that box), the KDE "Loading Desktop Settings" seems to stall -- login
waits at that point for about 30 to 60 seconds, then proceeds to a
blank desktop with _only_ the blue-and-curved-lines desk image and a
white cursor arrow. The mouse moves the arrow around but left, right
and middle click do nothing. No context menu appears. My desktop icons
are gone. No task bar at all. Alt+F1 does not bring any task bar up,
either.

Any ideas what happened?

How can recover my normal desktop settings and get back to normal on
that computer?

Thanks,

Roger