I know you're asking for way of listing avi files in Windows 7 by the codec type?
Did you know you can use VLC to analyse what codecs are in the clip your playing?
Drop your avi on then pause it,. go to tools Codec Information, then Statistics if you need more.
Problem>some will not play on my media centre<<
Install a codec pack,, or ffdshow and a divx player so that windows media center also supports them,
http://www.videohelp.com/tools/ffdshowsame problem here
http://shark007.net/forum/Thread-Windows-media-center-will-not-play-some-AVI-files-Windows-7I use Super video converter to recode them to a better divx anmd or Virtual dub
http://www.videohelp.com/tools/SUPER