If you’d prefer an even lighter option, try the unofficial QuickTime Alternative, which runs on Windows XP, Windows Vista, and Windows 7. If you don't have an iPod or other Apple-branded device and all you want is the ability to play QuickTime files, go to Apple’s QuickTime download page and choose the QuickTime-only option (don’t select the QuickTime with iTunes option, which includes the full, bloated iTunes installer). QuickTime is required if you want to use iTunes. The big selling point is support for the QuickTime movie (.mov) format, via the standalone player or an embedded ActiveX control. QuickTime is Apple's multimedia framework, a collection of codecs, plugins, DLLs, and several players designed to help you play back digital media files in most popular formats.
Here's an unvarnished description of each installer:
