Quote:
Originally Posted by
lordcloud 
Manned intergalactic space travel, floating mountains, Living planet, ten foot tall aliens......yeah, I will.
While there is always some fact mixed in with fantasy in a fantasy movie, to try and argue the plausibility of events in a world that may or may not even obey our laws of physics is entertaining, but no real conclusions could ever be drawn.
By your definition, there are really no sci-fi movies. 2001 is a fantasy because aliens put the monoliths on our planet and the moon. Dr. Michio Kaku, a world famous astrophysist, has said that that is the only plausible way to colonize and explore our galaxy in the foreseeable future.
My definition of sci fi is anything that is plausible. Wizards doing magic, fairies, etc. are fantasy. Aliens, space travel, new age technology, etc. are sci fi. You've got to draw the line somewhere, otherwise you'll delete an entire genre of film and literature.