I really liked Windows 7... since it was an overall improvement from Vista (which was scary!), and I sort of like Windows 8, but I am none-too-impressed with some of its features...
Well another thing I like is that my 2nd monitor is actually fully functional now. Before it was just something I can drag windows to and only use the bottom task bar programs. But now I can access the start menu and other apps on it without using my main monitor for all for that.