The one film that I'd actively petition to get remade (if I weren't so apathetic) would be Van Helsing.
So much potential squandered on a crappy story that would barely be passable in a computer game.
I'd also second the idea of rebooting Mortal Kombat. The mythology (as convoluted as it became) was one of the main things that kept me buying the games, even though I sucked at them. The Legacy web-series is okay, but a little hit-and-miss, and I wouldn't necessarily say no to the Nolan-esque Rebirth concept that first appeared on the web.
But it would be cool to see a movie (or a cable-TV series) that actually tackled the history and tried to create a coherent, textured story with these characters and this world (it can be done - oh yes! - it can be done). Imagine, it could be like Game of Thrones, but with ninjas and four-armed bodybuilders!