Husband and Wife

Already at beginning of movie:

Ray and Annie Kinsella
(Field of Dreams)

Victor, earl of Rhyell and Countess Hillary of Rhyell
(The Grass is Greener)

Peter and Melanie McGowan
(How to Kill Your Neighbor's Dog)

Others not pictured:

Mr. and Mrs. Bennett
(Pride and Prejudice)

Thomas and Charlotte Palmer
(Sense and Sensibility)

Become married during movie (wedding shown or not):

Billy Bigelow and Julie Jordan

Lieutenant John Dunbar and Stands With a Fist
(Dances With Wolves)

Prince Charmont and Ella
(Ella Enchanted)

Dr. Victor Frankenstein and Elizabeth

Curley and Laurie

Charles Bingley and Jane Bennett
Fitzwilliam Darcy and Elizabeth Bennett
George Wickham and Lydia Bennett
William Collins and Charlotte Lucas
(Pride and Prejudice)

Edward Ferrars and Elinor Dashwood
Colonel Brandon and Marianne Dashwood
(Sense and Sensibility)

Edward Cullen and Bella Swan
(The Twilight Saga: Breaking Dawn)

Frank Beardsley and Helen North
(Yours, Mine, and Ours)

Implied that they're going to be married:

Archie Leach and Wanda Gerschwitz
(A Fish Called Wanda)

Sam Baldwin and Annie Reed
(Sleepless in Seattle)

Joe Fox and Kathleen Kelly
(You've Got Mail)