Windows 2000 is a good home operating system. It starts up and shuts down extremely fast on a home network with no customization/optomization. It's compatible with just about everything but iTunes. It will also run very well on just about any computer system made in the last 15 years, with just about the only optomization needed being the occasional run through the start-up processes and services.
If an OS requires little maintenance, runs fast, and is compatible with most software, isn't that the definition of a good operating system?
And with Windows 3.1, you can't do everything on it, but I still use it for a lot of my Internet browsing, Solitaire playing, and word processing.