Could you also tell me how far the hotel is from the terminals and if I'll need transportation to get there after landing? Looking for a shuttle or a taxi with my suitcases at 1 a.m. is a whole other ordeal. I want to know how easy it is in practice.

I actually stayed there last year. I arrived late and had an early flight the next day. The Melia is the only hotel located directly within the airport complex. It is right next to Terminal 4, and you can walk there. I read this information on the Madrid International Airport (MAD) site before my trip. After arriving at Terminal 4, I followed the directions and reached the front desk in about ten minutes. At 1:00 a.m., that's a real lifesaver because you don't have to go anywhere. The rooms are decent - not luxurious, but clean, comfortable, and, most importantly, quiet, even though the airport is nearby. I slept well during the few hours I had.