Logon, Desktop Icons, Taskbar & Menu text

Archived from groups: microsoft.public.windowsxp.help_and_support (More info?)

This morning a did a disk cleanup with McAfee Quick clean. It was a routine
procedure so I didn't do a backup (famous last words...). I rebooted my
computer later in the day and now my logon screen, desktop, taskbar and some
menus have what looks like hieroglyphics instead of the correct text. There
are question marks, squares, angles, etc. in place of the words. The desktop
icons are there, but not the words. I can get into the programs and most of
them are fine except for the menu bar, which has the same symbols as the
desktop. If I switch users, the logon screen is ok and I did get the desktop
to look normal for a few minutes (by switching back to the previous user),
but rebooting the computer put it back to the messed up state. All of my
data files are fine (the desktop folder looks OK, too). Could the registry
be messed up? I cringe at the thought of reloading Windows because I made
it through SP2 without any problems. Any ideas?