These are quotes from what is reportedly the last Rumor Central column by "Spencer F. Katt" from eWeek magazine (December 15, 2008 issue, pages 48 and 49).
Windows 3.0 - the first usable version of Windows
Windows 3.1 - the first of Windows to actually work
Windows 95 - the first version of Windows that anyone would actually want to use
Windows 98 - the first version of Windows that no one actually needed (soon to be followed by many more, including the ultimate unneeded OS, Vista, which would supersede.........)
Windows XP - the first version of Windows that enabled productive work to be done.