"I'm looking up at the street and I'm seeing the sign for `The Lion King,' and I'm standing here and I'm thinking, `I had never thought in a million years I'd ever be standing in Broadway and talking about something I'd written for the stage," said John, beaming with pride.
John, accompanied by partner David Furnish, said he'd rather write a musical than record an album because he likes having a story line and characters.
"I love it - but I've got a lot to learn," he said. "I'm a novice at this."
"Billy Elliot," at the Imperial Theater, is based on the popular 2000 movie about a young boy who longs to dance but lives in the bleak coal-mining area of Northern England. His story is set against the backdrop of a bitter miners' strike.
"It's a triumph over adversity. It's something beautiful coming out of something tragic," John mused about the show, which has had successful runs in London and Sydney, Australia.
The role of Billy has been cast with three actors - David Alvarez, Trent Kowalik and Kiril Kulish - rotating the physically demanding part.
Joining John at Thursday's performance: Barbara Walters, Rosie O'Donnell, Ron Howard, Rachel Weisz, Kevin Spacey, Mayor Michael Bloomberg and tennis legend Billie Jean King.