My favorite guest stars - by a large margin - were Ronald and Benita Colman. They, especially Ronald, were so funny every time they appeared on Jack's show and the writing seemed to rise to an even higher level on those shows. If you've seen A Tale of Two Cities, you know that Ronald Colman had wonderful comic timing - even in an otherwise serious movie. But in many of his movies, like Lost Horizon, his comic gifts were rarely used. But he and Benita were tremendous on Jack's show. There were so many great shows but my favorite may have been when Jack tried to get Ronnie to co-star with him in a western. Just about every moment was hilarious, from Ronnie describing his past history to Benita ("Yes, Benita, I plunked a mean banjo; I was England's answer to Frank Remley), to he and Benita reading from that god-awful script Jack brought over ("I reckon I do, little lady, I reckon"), to Ronnie lamenting how others can look out their windows and see beautiful vistas, while he and Benita look out and see Jack luxing his undies. Every show with the Colmans was sublime.
The most disconcerting guest star for me was Bing Crosby. Now Bing was funny and an entertaining guest (and, my, what a singer!). But whenever he or the cast would talk about Bing's family, I can't help thinking about the real Bing that the audience, of course, knew nothing about, but of whom we know far too much.