Hi Melinda!
Thank you for visiting the Moms Panel!
Looking at crowd levels and weather for early March, you will find average attendance, which means there will probably be lots of people around, but lines are still very manageable. Average high/low temperatures are 79/56 with rainfall of around 3.5 inches.
Fall would be my favourite time to visit, with the week before Labor Day until the start of Epcot's International Food & Wine Festival (starting September 28, until November 12 this year) enjoying low crowd levels, and high/low temperatures of 90/72 for September, with 5.8 inches of rain. Crowd levels fall again after the Food & Wine Festival until Thanksgiving week.
Disney's Art of Animation Resort looks spectacular, and there is always something special about staying at a brand new resort. Your transportation system from this resort is by bus. The resort is closest to Disney's Hollywood Studios, and Epcot - a short 15 minute bus ride. To Disney's Animal Kingdom the bus ride would be around 20 minutes, and to Magic Kingdom park 22 minutes. Please remember that all travelling times are approximate, and don't forget to add waiting times at your bus stops. There are, however, no theme parks within close walking distance, as they are for Disney's Beach Club Resort.
If you have any other questions, please come back and ask me - I would be happy to help you plan your magical vacation!