Hi Shelley!
You are so lucky to be travelling at a time with super low crowd levels! As most kiddos will be back in school, you will see a dramatic drop in crowds at all four theme parks. Both resorts are fantastic; however, I haven't had the chance to actually stay at
Disney's Art of Animation Resort. On the other hand, I absolutely adore Port Orleans Riverside and highly recommend it to absolutely anyone. The rooms have all been recently renovated and there are so many activities on site that you may never want to leave! The food court is one of the best on property and the table service restaurant has the BEST corn bread that I have ever tasted in my life. You will find two Queen beds in each room, which a huge benefit in my opinion. Can you tell that I love this resort?
That being said, Disney's Art of Animation Resort is brand new and the suites offer kitchenettes. This can be a lifesaver when travelling with kids your age. Unlike Port Orleans, AOA has its own dedicated bus line and you will never have to share with another resort. The major drawback that I see for your family is that your mother would have to sleep on a convertible bed. The beds are state of the art and are advertised as being "comfortable." I'm sure that your kids will adore the beds, but I'm not so sure about your mom. I think that you will find more privacy at Port Orleans, but it sure is tempting to stay at a brand new resort. Honestly, I'm sure that either option will be awesome for your family!
Much pixie dust,
Jackie S.