Very hard to say, but any of the three mentioned in each category, will be a pleasure to hear at any time:
Classical:
Mozart: Clarinet Concerto (particularly the adagio movement
Schubert: D 856 String Quintet
Shostakovich: Piano Trio No. 2
Jazz:
Sonny Rollins: "St. Thomas" (from "Saxophone Colossus")
Coleman: "Lonely Woman" (from "Shape of Jazz to Come")
Gillespie: "Things to Come" (from "Reunion Big Band" (live performance))
Pop/Rock
Morrison: "Into the Mystic" (fromn "Moondance")
Orbison: "Blue Bayou" (from "In Dreams")
Mott the Hoople: "All the Young Dudes" (from "All the Young Dudes")