I found a recipe here which looks pretty good and has you bake the entire pumpkin in the oven with the stew inside. As opposed to this one which has you cook the stew in a pot and then serve it in the pumpkin when it's done. I think baking it in the pumpkin would make it more flavorful.
Also I was considering taking any recipe that calls for celery and replacing them with turnips, since someone doesn't like celery. Turnips are supposed to be flavorful. I don't really know what else would be a good replacement.
* And if you have any other recipes for Halloween, appetizers or anything, it'd be cool to hear.