You and I by default. The other ones are just bad, bad songs. You and I can be altered and then be made listenable. The same can't be said for the other two.
I think a lot of people are choosing "Yoü and I" because it was a single and it is the most recent of the three.
My personal favourite is "Brown Eyes" which sounds like it was inspired by Queen or something. I love the intro too!