Actually, you were specific enough. When I went to the profile, there were Standard IDE controllers for IDE 1 and 2, and another more specific-looking one that didn’t seem to have the option of changing. Since I couldn’t change it, I thought if I’d delete that, I’d be left with the generics. When that didn’t work, I tried deleting the lot of them, which I’ve been moderately sucessful with in other types of drivers. Not this time.
So, either I 1) didn’t know what I was doing, or B) had an odd configuration (more likely B). So, future upgraders, try what cstamets suggested first, if, for no other reason, repairing Win takes at least half an hour.