Do you have Beta Player? I consider it one of the best apps for watching movies on. You should be able to download it at
A great application for converting video is Auto Gordian Knot or AutoGK this is a also a free application. You can find it at-
http://www.pocketpcfreeware.com/en/index.php?soft=1080
http://www.free-codecs.com/AutoGK_download.htm