Well first of all I'd love to see "The Starry Night" By Van Goth, as he is the artist I love the most. And that painting is one of my all time favorite. I don't no why but it seems like it is the work that is a perfect expression of his turbulent state-of-mind. The colours are unbielivebly great. And that painting makes me feel blue and melancholy. But, like, in a good way.
And a second painting I really want to see is Sargent's "Carnation, Lily, Lily, Rose". It is the one that always makes me feel better and somehow calmer and more relaxed. There is so much serenity and happiness in it, that it is impossible not to like it. And if even a reprodaction makes you feel that way, I'd love to see what a real one can do.