Also of interest, running "SFC" today detected that Setupx.exe in the windows/system directory has become corrupted (on every machine in the house). It did not detect that OLEAUT32.dll was corrupt, however, though the latest nVidia driver wouldn't install until I replaced that file.
Replacing Setupx.exe did not fix the funky Internet Explorer problems that have plagued us forever, as I hoped it would. To be honest, I don't even know what that's used for.
So many residual virus and spyware problems. Remind me to install XP when I get back from the conference.