Sophie Marceau would be a good choice as Sophie, and John Rhys Davies would be fabulous as Teabing. Good call, Zaius.
I think it's funny that Tom Hanks (48) is too young but Harrison Ford (62) is too old. I actually pictured Langdon as being somewhere around 50, but I definitely think Harrison Ford could carry it off. Pierce Brosnan is an interesting suggestion, too, but I don't know that he could completely lose his accent, nor look rugged and bookish enough for the role. As much as I love Eric Bana... he's definitely too young at just 36.