The 1997 movie that features a significant storyline involving a wedding is "My Best Friend's Wedding," a romantic comedy directed by P.J. Hogan. The film tells the story of a woman who, by a promise made years earlier, is supposed to marry her best friend in three weeks, even though she doesn't want to. She tries to sabotage the wedding and win the man she should have married all along. Here is a poster of the movie.