Win XP cannot uninstall any program

All,

One of our sales reps left to take another job and, as is normal, I clean up
their laptop software-wise before using it elsewhere.

On this laptop I can't uninstall anything. The Add/Remove programs shows
the complete list of installed programs, but there are no Remove or Change
buttons to click on for anything. I have signed on as 2 different users,
including Administrator, with the same results.

A virus scan shows nothing, Ad-aware and Spybot have both been run.

If I look in the registry under
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall, it's
completely empty.

Anyone seen this before?

Thanks.