"We are flying into Orlando at night and we are staying at the airport hotel that night. The next day we have reservations at the Grand Floridian. Since we aren't renting a car and check in isn't until three, we will be able to drop off our luggage?"
Kathy, absolutely, yes. Just go to bell services when you get there. In fact, they'll probably even ask you when you check in if you want, at the Grand Floridian, bell services is right there.
They'll probably ask you if you want to leave your luggage and you just leave your luggage with bell services. They will deliver it to your room and you go to the parks, you enjoy. Happens all the time. All the time. Not a factor at all. Very simple.
Bottom line is, yeah. Just drop your luggage off with bell services at the Grand Floridian. When your room is ready or when you're ready to, when you're through in the parks, even if it's 11 o'clock at night. You go back to your room and you just call bell services and they'll bring it right up.