Did you know that if you toss your old Jack-O-Lantern in the trash the ghosts of a 1,000 plagues will haunt your home next year on All Hallow's Eve?
I read it on the internet and they are not allowed to put anything on the internet that isn't true so take my advice, compost that squash.
During most of the year I'm a big advocate of chopping things up to speed the composting process, but with time on our side most whole items will breakdown before the compost is used next spring. Just be sure the seeds are removed before adding Jack to the compost, unless you're into suprise pumpkins popping up in the garden. Let the seeds dry on a baking sheet and mix them into your seed mix for the birds on those cold winter mornings.