Windows Movie Maker 6 is bundled with Windows Vista, just like Windows Movie Maker 2.1 is bundled with Windows XP. But Windows 7 does not come with Windows Movie Maker,
but you can install Windows Movie Maker 2.6 for Windows Vista,on Windows 7.
Windows Movie Maker 2.6 is made for Windows Vista computers that do not have the hardware to run Windows Movie Maker 6. But you can run both Windows Movie Maker 6 and 2.6 alongside each other on both Windows 7, and Windows Vista.