Here is a Halloween set that I created on Poloyvore it will give you an ideas of the the things that you will need for a bewitching good time at your Halloween party.
Halloween Party Invitation Personalized Invitations by Susang6
Design invitations online at Zazzle.
Decorate the night before or the morning of the party, set up the buffet table so that all you need to do is serve the food when it is time for the guests to arrive. Organize the party music. Select some spooky tunes to set the mood of the party.
You can rent the room, and they will provide the food. However you may have to bring your own alcoholic beverages. For more information, search the haunted houses in your area.