"Things Are Swingin'," sings Peggy Lee,who opens an hour concert spotlighting her hit songs and the sections of the orchestra-brass,strings,rhythm and wood winds. Peggy offers "Fever" and "You Fascinate Me So" with the rhythm section:Max Bennett (bass) Lou Levy (piano)Mundell Lowe (guitar)Jack Sperling (drums)and Francisco Aquabella (bongos). Jean "Toots" Thielemans plays "Blusette," his own composition,and switches to harmonica to back Peggy on "Makin Whoopee."