I know it is long after Halloween, but I still have a few movies to mention, like Die Monster Die!. This 1965 American International picture starring Boris Karloff takes the outline of its story from H.P. Lovecraft's Color Out of Space.
It starts with American Nick Adams arriving in Arkham England (must be what the Arkham in America is named after) and meets a hostile reception when he says he wants to visit the Witley Manor. It seems that strange things are happening there. Nick's girlfriend, the daughter of the family is a normal young woman. But her mother is suffering from a strange aliment, the butler, Terence de Marney, is a bit peculiar, and her father is Boris Karloff, confined to a wheelchair.
The manor itself is perhaps the best part of the movie. The director, Daniel Haller, was art director for a number of Vincent Price films, and it shows. His sets are sumptuous and beautiful. Other than that, there is not a lot to recommend this.
Other than a few Cthuloids!