I showed Charlotte your post and she loved your suggestions. 
Glad to hear it!

Princess Bride she has seen and is one of her all-time favorites. She has seen Charade (one of my childhood favorites) but doesn't remember it well. And apparently she saw Singin' in the Rain and Penelope without me. 
Regardless, I can pretty much guarantee that Audrey Hepburn will have some representation tomorrow night. (Along with John Cusack; her one request for our marathon is Say Anything.)
If
Princess Bride is an all-time favorite and she's requesting
Say Anything, she clearly has
excellent taste in movies.

Glad to hear you'll probably be spending some time with Audrey, too!
A few other ones I thought she might enjoy:
The Man from Snowy RiverThe Scarlet Pimpernel (the one with Anthony Andrews, Jane Seymour, and Ian McKellan)
Oh, and has she seen
Ferris Bueller's Day Off??