Bridge to Terabithia!!!! I cried so hard I got a case of hitch sobs after. Anything to do with children dying or abused causes the faucet to turn on.
One I haven't seen in years, but made me bawl, was Not Without My Daughter, with Sally Field.
And then the typical animal drama, Where the Red Fern Grows, Old Yeller, My Dog Skip.
And the most recent movie to get the water works going was "Up". My daughter sobbed at this one too, great movie!
I'm going to have to re-rent What Dreams May Come. I loved that movie.