Opening titles give the name of the movie as "Ghost Busters" (two words). But in nearly all media/ads and even packaging/casing for home video releases, it is spelled as "Ghostbusters" (one word).
During the end credits, as the Ghostbusters are leaving in Ecto-1, three priests can be seen giving the last rites to a chunk of the Stay-Puft Marshmallow Man
There are no opening credits for this film, other than the title.
When end credits get ready to roll, Slimer attacks the camera and screen fades to black