HOLLYWOOD VARIETIES: The advent of television brings back vaudeville, as emceed by Robert Alda (who also sings "Be There My Love"). Acts like the Hoosier Hot Shots, Sandy and His Seals, Hector and His Pals, the Four Dandies and Twirl, Whirl and a Girl resurrect that great entertainment medium of the past. HOLIDAY RHYTHM: It's the top-tappin' fun-time of a lifetime when singer-dancer David Street bumps his head and dreams that he's on a trip around the world, and seeing great variety acts at each port. A Dixieland band, a mambo orchestra, a "Rhythm on Ice" show and even comedians Sid Melton, Peter Marshall and Tommy Noonan are among the dream world talent.