Season 1 and 2 of futurama converted to mp4 perfectly. They look bad on my computer but awesome on my zune 80. I used Any Video Converter Free, With mp4 settings at 320 x 240, video bitrate 512(the highest it will allow on the free version but still looks great), framerate 25, audio aac, 128, 44100, 2 channels, and basic A/V sync.
let me know if any of you use this as well and let me know your results, all of my wmv conversions with this were way out of sync. I also knocked off like 30-40 MB off the Futurama Episodes (approx 140 MB to 100 MB) going to try it on an avi movie and see how it does later.