I have a computer running it in my living room right now actually. Although it doesn't have a mouse...
I don't remember much about it when we actually used it seriously, because now my brothers and I just make jokes about it. Its interface is pretty different from the later Windows versions; there is no start bar or clock (there's a clock program though). The "desktop" holds the running programs, which always includes progman, which functions more like a modern desktop, except it has one of those omnipresent menu bars. If progman is exited, Windows shuts down. Then you have File Manager, which is sort of like My Computer, only completely different.