DOS was great (when I could remember how to use it!)
I had a PC nicked when I was a student - I'd taken the HD out when I went away for the holidays so the rest of it was just an insurance replacement, so no real worries. It was a P3 450 with I think 128MB RAM. The insurance replaced it with a p3 1GHz with 256MB RAM, better graphics etc etc, and when I first got it it had ME installed. It lasted about a hour until I realised that all the games I wanted to run (I'd just bought the 1st Deus Ex) ran slower on the new machine than on the old one. Aweful OS!