As a rule of thumb, I tend to like any episode that involves a priest or a psychic.  "Shadows from the Grave" ranks as one of the spookiest CBSRMT shows.  Fred Gwynne adds weight to the role of the uncle and the third act provides a satisfying conclusion.  I enjoy stories that throw in everything but the kitchen sink such as "Hicktory, Dickory, Doom".  The story hints at the uncle's past but doesn't leaves the details to the imagination of the listener.  More than any other episode, this show called for a prequel which could culminated in the uncle ridding himself (sort of) of his antagonist.  I am reminded of another great spookfest, "The Church of Hell".  