Out of curiosity to see how good or bad a result one can get from converting these movies into videogames, I choose:
Akira (though the graphic novels might make the transition more gracefully.)
Fritz the Cat (like Leisure Suit Larry but with anthropomorphic animals? There is also a chance that it would be better than the movie, so that's always a plus.)
Dead Alive/Brain Dead (then again, Mad World may be close enough, only with no zombies.)
Shaft (True Crimes: New York City doesn't fill the bill.)
Bat-Man 1966 (The Dark Knight will be a game soon enough if it isn't already out there.), complete with the 'visible sound effects' and Robin's exclamations, all voiced by the surviving actors from the show/movie.
The Sound of Music. (A rhythm game...with Nazis!)
La Blue Girl (action adventure hentai game?)
Expelled: No Intelligence Allowed (Uncover the vast anti-Intelligent Design Conspiracy in the scientific community. PZ Myers and Richard Dawkins could be Bosses.)