Stick with file types that your version of Sonic can use.
But maybe this will use them -> Try http://www.dvdflick.net/download.php
Using Movie Maker to edit, and Sonic(Record Now) to burn to DVD. Should WMV file be usable in the burning to DVD?? Seems that anything using the WMV file is aproblem making usable DVDs that will play in other DVD players. Any suggestions?