Movie: A Kid in King Arthurs Court (1995)

Tagline: Joust Do It.
Trivia: Paloma Baeza, who played the younger of Arthur's daughters, Princess Katherine, is actually six months older than Kate Winslet, who played the older sister. That makes a five-year age difference with Thomas Ian Nicholas.
"Young Calvin Fuller is pulled into King Arthur's court by Merlin. His Mission: To save Camelot. To do this he must overcome the villian known as Lord Belascoe, train to become a knight, and rescue the Princess Catherine who has fallen in love with him. Ultimately, He must help Arthur regain his confidence before he can go home. Written by Kevin Modglin <kevin615@delphi.com>"