New answers tagged 2000s
Maybe it is Finders Keepers (aka The Finder), an australian TV show from the early 90's that matches your description.
There is also Little Monsters - the boy (Fred Savage, America's greatest actor for you Family guy fans lol) travels to the monster world under his bed, but has to return otherwise he turns into a monster himself.
Sounds like Jumanji, but it was based on an ancient board game which worked like a clock time, and not a real clock timer.
Sounds like it could have been the movie Sucker Punch and the man inside Scott Glenn. The girls are in a brothel masquerading as an orphanage, and the alternate world is induced from the girls performing a dance and is about them attempting to accomplish some aspect of their escape plan.
The film is Emir Kusturicas Underground Details see Wikipedia and IMDB. The film is available at Youtube: Part 1 Part 2 The end scene you mention can be found at http://youtu.be/9iBZ8d9lii4?t=1h11m40s
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