Every park does a rope drop, in MK it's the train coming in with characters and the mayor of Main St opening the park. At Epcot, it's the characters' double decker bus. At MGM it's the characters on one of the parade cars. At AK it's the characters on a safari bus.
Usually the ceremonies only happen on non-EMH days. On EMH days, they just herd you in to a specific area, do a countdown and CMs holding the rope lets it go and people are then allowed to do the mad dash to the rides.
Sometimes, when a land is opened later than other lands (like Toontown in MK) there is another rope drop ceremony at the entrance of that land. The characters come out, a countdown is done too, and the rope is dropped.