a search of the IMDb turns up the following for "king arthur's court"

Connecticut Rabbit in King Arthur's Court, A (1978) (TV)
Connecticut Yankee in King Arthur's Court, A (1921)
Connecticut Yankee in King Arthur's Court, A (1949)
Connecticut Yankee in King Arthur's Court, A (1989) (TV)
Kid in King Arthur's Court, A (1995)
Young Connecticut Yankee in King Arthur's Court, A (1995)
Unidentified Flying Oddball (1979)
(Spaceman in King Arthur's Court, A (1979))

None of these looks like Disney....