It's a lovely song, and if it has special meaning for you I can see why you would want to play it at your reception ... BUT ... It's not a good choice as a first dance for a couple who is less than expert. Given time (several months at least) and an excellent choreographer who can work with your innate abilities, you might be able to pull it off, but I would like to gently discourage you from attempting to learn a few steps and fit them in. The song has some extreme changes of tempo ... they are dramatic and moving in an emotional sense, but actually MOVING to those changes and looking comfortable while dancing would be extremely difficult. Even Fred and Ginger would find this one to be a challenge.
Use this one as background when you're cutting the cake, or posing for pictures, or something else ... but choose something danceable for your first dance.
Or ... it might work as the music for a "hug-and-sway" if you are really sure you have to use it. After all, it's your own wedding.
Best wishes for a long and happy marriage.