"I imagine that the idea of using more than one application at the same time was mind-blowing to DOS users..."
Meh... Depends. It was all a bit much for many users, but then getting them to understand the single user single app thing was often a bit of a challenge too. Getting them to save their work before shutting down the app to open another was a challenge...
Those with techie sort of minds jumped on this very quickly, like 'Why wasn't it like this from the beginning?'
Having said that, it was so bug addled and flakey, many of us went back to DOS and stayed there, peeping over the parapet at each windows 'update' until we finally gave in. I found I quite liked the win95 shell, but the flakiness drove me to distraction. Then I got my hands on a pirate (pre release beta) NT4, and never looked back.
So I must love Windows 7 then? Well, actually, I'm loving Ubuntu 10.10. I have it on my machine and the guest machine, and the child box and the wife box are both on XP. I've yet to see a single feature in vista or 7 that I can't live without, and the rather elderly hardware still works fine with XP.