If the video clip you're trying to play appears sqashed (too narrow) or stretced out (too wide), the easy fix is to just look at your computer monitor from an angle so the video appears correct. But if you want a more permanent solution (and not a crick in your neck), update the codec as described in "How to play subborn video files in Windows"), as a later version may fix the problem.
It's also possible that the aspect ratio of the actual video clip is botched. To correct this, you'll have to open the file in a video-editing program that can resize video frames. Although the Windows Media Encoder can crop frames, it can't stretch or shrink a video. To change the aspect ratio of a video clip, use River Past Video Perspective ($29.95,
http://www.riverpast...tive/index.php) or Open Video Converter ($25.00,
http://www.008soft.c..._converter.htm), or, for more control, try a more advanced video application such as Adobe Premiere Elements ($99.99,
http://www.abobe.com).