This video shows how to convert from 4:3 to 16:9 aspect ratio using VirtualDub
http://virtualdub.sourceforge.net
IMPORTANT: Only works with avi input, so if you want to use a video that is not in avi format you can convert it to avi with WinFF http://winff.org/html_new/downloads.html and then you can use this method
Download XVID (for compressing the video)
http://www.xvidmovies.com/codec/
