Film 53: Wallace and Gromit: The Curse of the Were-Rabbit
Another quick fix and possibly the shortest entry in the book. Sure, it's borderline - but it has a transmogrifying man-beast, mind-transferrance, a climactic hmage to King Kong, stylistic nods to Hammer and themes around the British class system and social standing.
That's a British horror film in my book (even if the money was American). So that's where it goes - in my book.