My favourite British horror anthology series is Thriller, created in the 70's. Like many other anthology series, there were some big name actors who became famous in the years following their appearance here. Paul Darrow, best known for playing Avon in Blake's 7. Helen Mirren, who needs no explanation. Donna Mills, Patrick McGee, and many more. Some of the stories are a bit hokey but some are just super.
https://en.wikipedia.org/wiki/Thriller_(UK_TV_series)
As mentioned, Hammer House of Horror is pretty good, too.