I ran across a patch Microsoft has written that I could download and install. It was called:
Microsoft Security Bulletin MS02-072 Print
Unchecked Buffer in Windows Shell Could Enable System Compromise (329390). It had two vertions or types for the download/install: 32 bit and 64 bit.
I poked around Windows a long time without finding whether I had 32 bit or 64 bit. (I'd hazard a guess it's 32 bit...but I don't know that.)
How do I find out which I have?