Molly-O,
We too, flew out of NH to Sanford. I assume you are flying Pan Am. I don't feel like getting into my gripes about the airline you are taking, but you may want to rethink.
As for Sanford, the airport is great. It is small. The first time we flew in, they were renovating the terminal and we had to walk from the tarmac and the baggage claim was out in front of the airport at the curb.
Now, the rennovations are complete and the airport is bigger, but easy. The drive from Sanford to WDW is about 50 minutes. The first time we flew there, we took Coach USA, which were busses. We had to wait two hours for them to fill a van with people to make their trip to WDW worthwhile. The driver was unprofessional, smoked in the van, and complained the entire time. I think one-way fare was $22.
Since then, we have rented a car for the trip. The drive is SIMPLE, and it allowed us to make a grocery stop.
ALAMO offered us a great rate, and you can drop the car off at the Alamo area which is literally just outside the doors of the airport and to the right. Simple. We have also used Dollar. It is slightly hard to find. YOu have to go outside, and walk left into another side building. Still easy, and offer decent rates.
We did not keep our rental cars the entire week. You can pick up a car at Sanford Airport and drop it off in Orlando. The Dollar site is just a short walk from Downtown Disney at the Courtyard by Marriot. They will pick you up at your resort if you need them to, and give you a lift to where you need to go (within reason). The Alamo site is at another DD Hotel, I dont remember the name.... again, easy to get to and from.
PM me if you really want to know our Pan Am story.... you may be better off not knowing!
Pan Am's RT for two is usually around $660, You could get Southwest from Manchester for the same price or less right into Orlando. 1029 and 2375 are direct flights from Manch to MCO, just a thought!
Enjoy your trip!
Holly