A couple times in the past I refreshed Win98 with a reinstall directly over the old system. That fixed some damaged functioning that had been at the quirky level of seriousness.

Then I went to dual boot and tried again. I cannot conclude that this was the cause of the problem.

Part of the problem seemed to be that I had not completely uninstalled and deleted the antivirus, AVG. But that still was not enough.

So I went to DOS and renamed C:\WINDOWS to C:\WINDOWS0. Then the reinstall worked and I copied some stuff (like wallpapers) over from WINDOWS0 and deleted it.