I highly recommend "Sleepy Hollow", a musical based on the Washington Irving story.  Written by Vera Morris with  music by Bill Francoeur.  Our community theatre group produced this on our small stage and it was a hit!  The music is great and the story is wonderful.  The climax is the headless horseman.  Our theatre is on the second floor of a historic building and bringing in a real horse seemed out of the question.  However, I contacted people I new that raise horses and they had a Sheltand pony that was able to walk up the steps and into the back of the audience.  The audience was astonished to see this pony walk around them and "chase" Ichabod out of the auditoium.  If you're looking for a great musical that can be produced on any size stage... and perfect for a Halloween season - then this is it!
Here's the link
http://www.pioneerdrama.com/searchdetail.asp?pc=SLEEPYHOLL