If a special time in your life were to be screened as a musical, which period would you select & what would be the opening number?

Let’s just take it as read for one cottonpickin moment here, that a musical were to be made depicting a memorable occasion in your life, i’m talking movies here folks. What song from an existing musical would you personally choose to be given the honour of opening this melodic masterpiece? One which you feel would accurately reflect your feelings/memories of that particular moment in time. Either the theme tune or simply the first song to be performed in the movie will suffice, both just as valid in my book.