Okay, since I really hate it when people figure these things out on their own
and don't tell anyone:

I ran the process explorer from sysinternals.com to see what was being
opened during the splash screen, and saw this in the list:

File    C:\Documents and Settings\sean\Local Settings\Application
Data\ApplicationHistory\devenv.exe.6262e30a.ini.inuse

I deleted all the files in the ApplicationHistory folder and I can now use
visual studio again.

Here's a little suggestion for Microsoft:

Document more fully what files your programs use, what the purpose of the
file is, and !!!WHERE THE PROGRAM PUTS THEM ON THE SYSTEM!!!!!

Or how about this?

When a program is "un-installed" it should either:
remove every file (and folder) it silently created during its install and
use --
or --
tell the user where those files and folders are so they can remove them
3rd party installers such as InstallShield typically offer this _HELPFUL_
option

Is this really so much to ask? A "re-install" or "repair" is really pretty
useless if it isn't going to clean up the damage it did the first time
around, the sloppy way that uninstalls are dealt with leads to an
accumulation of garbage in systems that simply doesn't have to happen with a
little attention to detail on the part of the people in charge of windows
development.

I just spent 4 days wasting time trying to get VS2003 up and running,
because it silently created and opened files in an -- apparently, you try
searching for any mention -- undocumented folder that, had I known where to
look, could have been cleaned out and I could have been working again in 30
seconds.

Thanks to Ken for taking the time to respond, kudos Ken!

Hang on! Hold the presses! Now that I already know what file I'm looking
for, here's a list of files in visual studio from the veritest certification
report:
http://cert.veritest.com/ReportFiles/Microsoft_VSnet_Preport.pdf

Of course, the report claims that the file that was keeping the application
from working was "properly left behind" on uninstall.

Application settings and history applicable only the application being
removed are considered "properly left behind"????? This is like going camping
and leaving the campsite littered with your empty beer cans on the way out.

Perhaps I have a different view of "well behaved" programs, but in my view,
a program that on uninstall leaves behind a hidden, corrupted configuration
file that prevents the application from being able to function when
re-installed is not "well behaved", and the file was not "properly left
behind".

If anyone has the resources to do better, Microsoft does. This is just plain
sloppy.

Sean