Forbes has a list of the top grossing on-screen couples. Bella/Kristen & Edward/Robert make the top 5.
Rounding out the top five are Robert Pattinson and Kristen Stewart in the Twilight movies. While romance might take a backseat to action in many of the movies on our list, it's the driving force in the Twilight films. It doesn't hurt that Pattinson and Stewart are also a couple in real life. So far the movies have earned $1.8 billion at the global box office. The last book, Breaking Dawn, has been divided into two movies. The first will hit theaters this coming November.
Ahead of them are Rupert Grint & Emma Watson (Harry Potter at #1) Viggo Mortensen & Liv Tyler (LOTR) Orland Bloom & Keira Knightley (Pirates) Leonardo DiCaprio & Kate winslet (Titanic & Revolutionary Road.)