Hi Kristin,
How exciting to be taking little ones for their first trip to Walt Disney World! I have to say, you have picked a great resort.
Disney's Art of Animation Resort is amazing with a theme that immerses you in Pixar and Disney movies. It is bright, colorful, and simply amazing!
Disney's Art of Animation Resort will provide plenty of activities to do on your first night. I absolutely recommend that you spend the evening at the resort. Settle into your room, and then go explore. The lobby is bright with colors and has the Pixel Play Arcade. The pools at this resort are amazing. The Big Blue Pool is huge, and you can even hear sounds underwater! Since you are going in January, it may be a bit chilly; however, the pools are heated, and I have always found that young children want to hop into the pool no matter what the temperature! You can also enjoy the Righteous Reef playground in the Finding Nemo Courtyard. Have a meal at the Landscape of Flavors food court. If you still have energy, you can take in a Movie under the Stars shown in the Lion King Courtyard - simply check the Recreation Guide that you receive upon check-in to find out the movie that night. It will be bedtime before you know it!
I hope that these thoughts are helpful, Kristin. Have a wonderful time planning your vacation, and please do not hesitate to ask if you have any further questions!