Some of the scenes in the first movie were inspiring and downright moving. Most of not all of that was due to the soundtrack which perfectly meshed with movie. The scene where you first hear, "Gonna Fly Now" with it's climax on top of the steps overlooking the city almost made you ready for the ring yourself. Of course, like many movie soundtracks, the song is totally encased in the amber of it's 70's kitschey-ness with the chorus and all, but in it's day, it worked, and really that's all that's necessary.
Bill Conti already had some success as a writer of soundtracks, but Rocky put him on the map. He wrote for many movies and TV shows throughout the 80's and 90's.