First, you need to convert the video file to mpg. I have found an application that does just that - VideoReDo - http://www.videoredo.net/msgBoard/showthread.php?t=1984

A great thing about this is the ability to edit videos (cut what you don't want) and even has a "ad dectective".

I have also heard that Nero 7 will do the job.

After that, use Media Converter to make it compatible with the 770. I could not get MC to work, but I did find this that did work, and work quite well (and fast!). It has settings for the 770:

DVD Catalyst - http://www.pocketgear.com/software_detail.asp?id=14418

It's not free, but it is cheap. There is a evaluation copy to see if it will work. It also has the advantage of ripping a DVD directly to the 770.

I just copied an episode of American Idol on the 770 as a test. The whole process took about 30 minutes. Using Catalyst's best setting for the 770 (29.97 fps, 320x240), an hour equated to over 100mb. The quality was quite passable even at 200 kbps and 1x pass.