From what I hear there's lots of wmv files that are porn. If you are after porn then stick with it. For movies as in full movies, stick with avi & mpg/mpeg since these tend to be the best in quality & most reliable (unless you can only find what you're after in wmv format.) Films should be CD size (ie: 500-700 MB) avi's & particularly the divx tend to be very good, they can be good resolution yet smaller than the others in size or same size but better quality.