Hi Mehgan,
How exciting your first trip!!!
You really can't go wrong with any of the resorts. The resorts on the monorail line make it a little easier getting around to certain spots. There are awesome features to each of the resorts. Take a look at what you would like to experience and then choose from there.
I would highly recommend character dining. There is no other experience quite like it!
HERE is the link to see what is available. I am sure your little one would love to dine with the princesses! My kids love Chef Mickey's as well!
Your princess will love the Magic Kingdom! There will be so much for you all to experience. Make sure to pick up a Times Guide once you arrive so you can see show, parade and firework times, as well as character meet & greet locations/times.
Make sure you and your husband choose activities you would like to experience as well. Visiting Epcot is always fun and entertaining. Walking around the world and experiencing the different countries is a great way to spend a day.
You will have such an incredible time.
Take a lot of pictures and make sure to pick up an autograph book when you arrive so your little one can get autographs from the characters.
Thank you for your question.
Wishing you a very magical vacation!
Carrie