The Magic Kingdom. The Magic Kingdom is the one park that is set up for the whole family and is primarily for the younger ones but it still has some attractions for those that crave the Science Fiction experience.

Space Mountain

Space Mountain is the name of a space-themed indoor roller coaster attraction located at all five Magic Kingdom-style Disney Parks. Although all five versions of the attraction are different in nature, all have a similar domed exterior façade that is a landmark for the respective park. The first Space Mountain ride opened in 1975 at Walt Disney World Resort in Florida, and similar attractions were then eventually built at the other Disney parks.
See Wikipededia for full ride description