OMG! This is doing my head in somebody please help me!?

In the early 90's there was a kids gameshow type thing, it had a lift with a talking head on a computer screen which took the contestants to different places in this house to complete tasks, eg. swimming in a giant bowl of soup stuff to collect foam letters or something. Then at the end, the best person (most points etc), went to this dark room on a grid thing where this darth vader guy had to try to get the kid out by standing on their square & making them dissapere in his cloak. There! Random i know but somebody has to know what this program was called for my mates & own sanity lol!