From the main menu of the "In Her Shoes" DVD, choose Special Features. From that menu, highlight Main Menu and then press the left arrow on your remote. A window on the left then changes to the Theatrical Poster of the 1959 Joan Crawford film "The Best of Everything" Hit enter and you'll be treated to the original theatrical trailer of the film. The two films have some similarities, so I assume that's why it's included on the In Her Shoes DVD.
All easter eggs were generously submitted by SirDonk