As for the TOD :
I love Gertrude Neissen (sp?), Ruth Etting, Fred Astaire, some Helen Morgan, early Bing Crosby (accompanied by the theatre organ no less!!), and for variety there were some incredibly quirky tenors with extremely nelly voices. Paul Small was one of them.
But one of my all time favorites (that was mentioned earlier) was Ethel Waters, especially singing "Suppertime." It can still put me in tears.