If u make or edit video on windows movie maker, u need to save the video as avi format, then convert the avi video to high quality flv video with E.M. Youtube video, then upload the flv video to youtube. then u will get high quality video on youtube.
How to save video as avi or wmv for uploading to youtube on Windows movie maker?
http://www.microsoft.com/windowsxp/using/moviemaker/create/savetopc.mspx
http://www.google.com/search?hl=en&newwindow=1&q=E.M.+Youtube+video&btnG=Search
(1)Download youtube video fastly and easily;
(2)Burn Youtube video to CD/VCD/SVCD/DVD disc;
(3)It can search any flash video from many websites at the same time;
(4)Convert flv video to any audio include mp3, wma,wav,ac3,mmf,amr,ogg,aac..., to any video formats include 3gp,avi,wmv, mpg,mpg4,asf,swf,h264,mov,jpg, that can be supported by PSP,iPod,iPhone,Apple TV video,iTune,mp3,mp4,Zune,Cellphone,Digital camera,DV,CD/DVD/VCD/SVCD.
(5)List all cache flv video;
(6)It can also repiar and capture RTMP video streams.