Ive been playing with MS Movie Maker 2 (free).
Dont know how to make it do batch though. Doubt it can.
Heres a quick clip I made to promote one of my sites.
Interesting thing too is that it is very easy to embed URLs in these files so at the end of the video you can have it open any website. (I havent done this with the following video).
http://www.1dollarvideo.com/1dollarporn_preview.wmv