As an aspiring filmmaker, I've often thought of what my dream cast would be if I could get the MI movie rights. The following are the names I've landed on most frequently/recently.
Guybrush - I've been saying NPH for years. He's one of the most brilliant and versatile comic actors working today, and his voice, while not identical, is pretty similar to Dominic's.
LeChuck -
Tom Wilson. A very funny man who's already my favorite movie villain, so why shouldn't he be my favorite video game villain? He can switch from funny to intimidating instantly, which I think is important in a LeChuck.
Elaine Marley - Amy Adams is the thought that crosses my mind the most, although I'm not sure if she has quite the right presence.
Carla - She may not look EXACTLY the part, but Gina Torres from "Firefly" could pull off the "badass" aspect.
Meathook - Bruce Willis. The man can be very funny in the right role.
Stan - either James Roday from "Psych", or Will Arnett
Herman Toothrot - Eric Idle
Voodoo Lady - Aloma Wright (Laverne from "Scrubs")
Largo LaGrande - Warwick Davies. Obvious, perhaps, but still.