Flood, you can just try looking up "DVD extractor" or "VOB ripper" or any combination on a search engine to get a program that extracts the DVD's VOB files to editable video formats. There is a program bundle that I used to have that had all kinds of DVD ripping utilities, and a few of them ripped the WC4 DVD's VOB files relatively well.
I've been wanting to make a "theatrical" version of WC4. Extracting the original files and editing them together is the easiest part, and to most people it seems that it would be easy to edit the scenes together, it would just take time out of their lives. The problem is that most scenes don't have anything leading up to them; scenes mid-mission just pop up, with no shots of the battle before, and most of the scenes on the various carriers just start with no transistion, and just end with Blair walking away.
If one would to cut WC4's scenes together, it just would be a series of random scene changes of conversations and mission briefings, with a couple of the major film sequences already compiled (the Black Lance base scenes, or the easily spliceable Grand Assembly scene). The most logical thing to do would be to add scenes taken from the in-game engine, but doing that would severly reduce the quality of the final product.
I've really thought about doing a project like this, but it would require a lot. It would need new 3D scenes, a lot of sound editing and manipulation, and let's not forget excessive video editing. Although I've really wanted to do this project, it's simply not feasible at this stage for me and my scheduel. I'd be willing to help anyone who tries it, but I know I won't be doing any work for it by myself for a long time.