This is really cool because then you don't need to use Apple Quick Time player because it really sucks, uses a lot of CPU than windows Media Player and your Quick Time videos don't look washed out any more.

Installing a Codec Pack

On earlier versions of Windows you can download Direct Show filter packs to do the same. The one I have tried is K-Lite Code Pack. It's free and works like a charm. You can download it from here:

The K-Lite Codec Pack also allows you to play Flash Video (.flv container) using Windows Media Player). So essentially, Windows Media Player is the only Player you'll ever need.

When installing, simply choose the default options, (that is no need to change anything), except for the options on one of the screen to width with thumbnails in Windows Explorer. When you get to that screen, you may want to check off the various file types for which you want Windows Explorer to generate thumbnails, such as .mov, .mp4, .flv etc.

Another thing you may want to do is associate Windows Media Player (instead of Windows Media Player Classic) as the application to use for the various files types.