I came from a family where my people didn't like rhythm and blues. Bing Crosby - "Pennies from Heaven" - Ella Fitzgerald, was all I heard.
Fred Astaire is the best singer of songs the movie world ever knew. His phrasing has individual sophistication that is utterly charming. Presumably the runner-up would be Bing Crosby, a wonderful fellow, though he doesn't have the unstressed elegance of Astaire.