Coco

This isn’t a Halloween movie (it’s about the Day of the Day) but it has themes about grief, aging, and family (be prepared to cry).

It has skeletons (but I don’t think it’s presented in a scary way) and covers the topic of death; it may be too heavy /complex for younger children (but you can look at IMDb for a Parent’s Guide to see if your child would be okay with it).

I think it’s one of the better Disney/Pixar movies from the past few years.