If you select the movie clip and convert it, like komputerkurt recommends, you should still be able to alter the movie clip in AS. Meaning you can make it go to and play a frame of it.
But it sounds like you don't need a movie clip, so in library you can select the object you want and right click; then select properties. From there change it to button instead of movieclip. Then from there (assuming you have each room on a separate frame) you would go to the separate frame.