Hi Candace! My birthday is January 2 and I have made it a tradition to visit Walt Disney World with my family because Disney is the ultimate celebration destination. We usually arrive on December 30th and stay through January 6 and while the crowd levels are high on NYE and New Year's day, I am excited to tell you that they decrease DRASTICALLY as of January 2nd. With that being said, I am pleased to say you have actually chosen a great time to visit.
If you arrive on the 31st, my personal recommendation would be to steer clear of the theme parks! This is one of the few calendar days on which the parks reach full capacity, and even close to new guests, sometimes before noon. While everyone else is over at the parks, my family enjoys leisurely experiencing all of the fine sights, sounds, and shopping offered at Disney's Deluxe Resorts and Downtown Disney for the day.
The Grand Floridian offers fantastic views of the NYE fireworks, which I must admit are the BEST I've EVER seen...anywhere... and I would recommend booking a late dinner reservation at
Narcoossee's for a memorable NYE dinner and some of the best views of the Magic Kingdom. Last NYE they featured a special Prix Fixe menu and reservations will book up fast, so be sure book online or by calling (407)WDW-DINE up to 180 days in advance. After dinner, if you hang around the resort until the fireworks, you will be able to find an incredible viewing spot from the resort's beaches, marina, or if timed correctly, right from your table at Narcoossee's.
Though it's hard to predict crowd levels, I think January 2nd through the 4th should be smooth sailing. The weather in January is usually mild, and in my experience the crowd levels are lower than usual with most attractions experiencing minimal wait times. Here's wishing you lots of pixie dust for a most memorable Walt Disney World vacation! -Amanda