I don't know what this movie was suppose to be about. There was no plot anywhere...
I only saw it once in the theaters, so I'm trying really hard to refresh my memory...
Tony Manero (John Travolta) lives with his working-class family in Brooklyn, NY. He has a job in a hardware store, but lives for partying and dancing with a bunch of friends every Saturday night. He and his friends seem to have no ambition or plans on what they want to do as they grow up.
He later develops a relationship with another dancer named Stephanie (played by Karen Lynn Gorney) who does have some sort of ambition and concerns on her life goals.
Later on in the movie, Tony realizes his life (which consist of mostly nightclubbing, dancing, and working in a dead-end job as a paint salesman) is going nowhere. He even consults his brother, who is a Catholic priest. This is especially affirmed when one of his friends commits suicide by falling over the Brooklyn Bridge.
It's amazing what you can remember if you take out the music and dancing sequences!
The movie critic Gene Siskel once said this movie was one of his favorite all-time films. He also claimed to have bought Travolta's white suit used in the movie through an auction.
The sequel "Staying Alive" came out as a follow-up to what happened to the Tony Manero character.
Hope this helps!