I've used and installed Windows 95 (a,b,c) and Windows 98 (1st, SE) and the usual life expectancy is six months, at the most, until either it becomes unfixable or crashes so frequently you may as well reinstall (it). Scandisk would begin to report "can't find last sector on drive x:" which was untrue. The system wouldn't boot. JPEGs would be saved as BMPs, and format c: it was.
But then for a year I had a clean run with no problems and the only thing that changed was that I no longer used Internet Explorer.
I told this to one of my friends.
"Oh. you didn't know that?"
"Well how many times have you installed it?"
"You going anywhere tonight?"
I nearly cried.