Well if you already have the movie (like a 700mb avi file) then there are a few free converters out there that will help them play on your windows mobile phone. I recommend Videora
http://www.videora.com/en-us/Converter/iPod/ Its free and it has a ton of presets for video size and quality. Just read up on the instructions on how to use it. For my phone, in Videora, I just use the ipod touch 2pass preset. Works fine and keeps the video file small.
For DVD to phone, you'll need a program that converts the video on the DVD to like wmv or mp4. I have software at home I bought, but I can't remember the name of it now. Googling should give you a large selection.