I don't remember much about the movie... a kingdom, a prince and a princess, a witch, which built a big clock, which made the time passing by faster than usual and people got older for hours. In the end the prince broke the clock with a stone from the princess' ring. Please help me find this movie

This was answered a couple of days ago over on imdb.com. It's a 1996 TV movie called To the Ends of Time with Joss Ackland, Christine Taylor, and Sarah Douglas (who those of us of a certain age recall fondly from Superman).