Hands down, "Mr. Holland's Opus" starring Richard Dreyfuss. Left the theater bawling my eyes out and didn't stop crying for at least an hour.
Next would be "Top Gun". Have seen it over a dozen times and still laugh, cry, and cheer in all the same places.
"The Holiday" with Cameron Diaz, Judd Law, Jack Black and Kate Winslet. The scenes between Winslet and Eli Wallach are pure Old Hollywood.
"Something's Got To Give" with Diane Keaton and Jack Nicholson. I'm not a JN fan, but loved their chemistry in this one...and the ending. A movie that turned out exactly as it should.
"Blind Side" with Sandra Bullock. Laughed and cried all through that one, too.
And reaching deep into the sands of time, "The Electric Horseman"...another movie I can watch over and over and never tire of. Always cheer when Redford turns the million-dollar horse loose, and laugh when Jane Fonda's character says "You did what!". ;D