I agree with
You've Got Mail - I don't own it, but I've seen it often enough to have the dialogue memorised :lol: and it's just so sweet and it makes you believe in love and all that. Awww.
I must say my all time comfort movie is
Amelie, though - it's quirky and cute and the two main characters are. Just. Too. Cute. And therefore completely perfect for each other. You feel sad? Put it on and you'll start believing in the world all over again when it's over

and wishing you had someone who was just that perfect for you, but that's something else.
And for something I don't own, but watch every time it's on - well, there are a lot, but I think the one I'll go for is
Eternal Sunshine of the Spotless Mind. It's sad - no doubt about that; it gets you into a funk afterwards; slightly depressed and melancholic. But somehow it's good, because the film is that good. Jim Carrey in this film was incredible, his was such a nuanced performance and he was the perfect mix of loser and yet still appealing. A loveable loser? Whatever it is, it worked. And Kate Winslet was perfect as the impulsive Clementine...it's smart (uncomprehensible, at times), sad, funny. And the song at the end of the movie, Beck's 'Everybody's Gotta Learn Sometimes'? Perfect. You don't notice it when it's played in the beginning (after the opening credits) but at the end it's just so absolutely right - in lyrics, and more importantly, in mood. It's sad, but it's comforting at the same time. I think I'm weird :look: