Use Your Computer, Don’t Keep Relearning It
Try Linux Mint, which has kept a consistent desktop environment and menu with each release. While by comparison the Start Menu, Taskbar, and Control Panel has been changed in each major version of Windows (except between Vista and 7). Consistency does not imply a lack of improvement: Linux Mint continues to be developed and improved, but not in drastic ways that force you to have to relearn how to use your computer again.
Note: it may look like the menu changed between Linux Mint 6 and 13; however, the other menu layout is actually just a click away.