When you say you're driving 2000 miles, that must be round-trip. No place in NYS is that far one-way. So let's just think about one-way, from NYS to WDW. DD and I drove to Rochester alone from Miami. Every year for Christmas and summer break. Sometimes we drove the whole way, sometimes we took the AutoTrain for a good part of the trip. The AutoTrain was part of our vacation adventure.
Make sure you have a spare tire in good condition. Take the car to a local place and tell them you're going on a road trip. They can check brakes, change your oil, check your water and fluids, check your lights, check your tire pressure, even rotate your tires. It would be very wise to have
AAA, just in case of a rare problem. And AAA will get you a discount at most any hotel you stop at along the way, plus some chain restaurants. AAA also has discounts for WDW resorts.
I bought a GPS, a Garmin Nuvi. It plugs into my car power. I have a cell phone. I have a large Atlas Book from a book store. I have a flashlight and fresh batteries. Your son can plug into something to entertain himself. Carry pillows and blankets for rest. Carry snacks and a small cooler for drinks.
From where you are in NYS, you need to have a general plan about how far you will go in one day. Use Google Maps, MapQuest or Bing Maps. They have a feature called "Get Directions." Type in your location, then a target location. For example, from Westchester NY to Magic Kingdom is 19 hours. It will show you the route on a map and you can print out the directions. If you don't want to drive 19 hours straight (who does?), then check out the distance to places in-between. Richmond, VA is 7 hours, distance remaining is 12 hours. Rocky Mount, NC is 9 hours, distance remaining is 10 hours. Fayetteville, NC is 10 hours, distance remaining is 9 hours. Using these 3 examples, zoom in on the map and look at the exits. Find exits that have a cluster of hotels with a cluster of chain restaurants, then use AAA or TripAdvisor to get rates and ratings. Look up hotel specials. You could be ready to make intelligent choices about where to stop by doing a little bit of homework.
The AutoTrain is a great help and very enjoyable. You could also take the Amtrak all the way and rent a car once in Florida. Whatever you choose, you have the company of many other ladies who have hit the highways successfully and confidently.