Rhapsody in Blue. It's the most popular song By Gershwin. Than, I would say "Summertime".
I got rhythm is also really popular, and I'll finish with Oh, lady be good.
Probably 'Rhapsody in Blue' and 'Summertime'. 'Summertime' is from the opera 'Porgy & Bess' and has been performed by Billie Holliday, Ella Fitzgerald, Sam Cooke and Janis Joplin.
George Gershwin: An American in Paris, Summertime, Lullaby, I got rhythm, Rhapsody in blue, Do Do Do, Left All Alone Again Blues, Walking the Dog - Beginner's Luck, Fascinating Rhythm,
