There was some mention above about a project that compiled the cut scenes from "Dark Forces." It was a project by Kaal-Jhyy, and it actually was a preservation of "Jedi Knight - Dark Forces II." He had two threads, which you can find HERE and HERE.
As for what you mentioned above whether a project should feature just the cut scenes, or combine the cut scenes and gameplay....I think it depends on the project and the game itself. On the original "Bounty Hunter" DVD MoveAlong and I put together, we only featured the pre-rendered cut scenes, but it made the story hard to follow. On our new 2.0 DVD, we show the pre-rendered cut scenes, the in-game engine cut scenes, and gameplay. I think the new "movie" we've put together is much better. I think showing at least some gameplay in a project couldn't be a bad thing.