I'm in love with this series of audio clips from NPR featuring filmmakers, actors, actresses, writers, etc talking about those movies they will watch again and again.
Of course, I'll never pass up the opportunity to offer my two cents. This list is the official "You've Got Mail" memorial list:
When Harry Met Sally... Anne of Green Gables Speed Only You
And NO, of course I could never pick just one. I could barely narrow it down to these!