You have asked me sir a very difficult question. I like so many. My favorites growing up were "Do Re Me", "Lonely Goatherd", "16 Going on Seventeen," "My Favorite Things," and "Edelweiss." How could I possibly choose? Although the songs chosen were great, I do think "Climb Every Mountain" has a lasting and uplifting message, so I am tempted to choose it.
edit: Oh, how could I forget "So long, Farewell"? *wonders if she lost her mind*