When we went last year for Halloween, only Wildcat was closed. I think they started their off-season maintenance early on that.
Halloween is a great time to go to Hershey. On the day we went, the weather was fairly nice, yet the Storm Runner line was never out of the station and it was only running one side too.
I have a tip for you as well. Look for the ticket booth furthest away from the entrance. Everyone lines up for the first one they see and the farther away ones have no lines at all.
Sue