I'm sorry that my suggestions haven't worked but (if you're seeking to save streamed video) you seem to be doing things the hard way to start with.
Streamed video (from Youtube and similar sites) arrives at your PC in FLV format. To retain optimal quality it's best to save the file in the same format, and then to play the files with a video player that works well with that format. Simply go here
http://keepvid.com/
and drag the 'bookmarklet' onto your links toolbar. When viewing a video you want to save simply click the 'Keep It!' button, renaming the file from the default name offered to your own choice of name and (importantly) adding the .flv file extension. (e.g. choose something like "banjo.flv")
To play your video files, use a decent media player. Both of these are far better than Windows Media Player and RealPlayer put together:
VLC:
http://www.videolan.org/vlc/
GOM:
http://www.gomlab.com/eng/
Chris