We just got back from our December trip and we rented a car for a week. We reserved on-line at alamo.com and used the mousesaver code of orless. I had a mid-size reserved, checked 2 days later and there was a mid-size SUV for about $100 less, canceled the other car and took the SUV. You can get picked up right at your resort by Alamo. Just call them anytime from 1 hour to day prior (I called 1 hour from time I wanted to be picked up and the driver came right on time) to when you need to be picked up and then wait where they tell you (for us at Pop it was in front of the building lobby) They drove us to the Car Care Center, since we chose to get the car from there instead of the Swan/Dolphin. We were in and out of the office in about 5-10 mins and on our way back to our resort, they even asked us if we needed directions back (the driver and also the desk help) to our hotel. To get back into the resort area at the gate, you just have to scan your room key.
Getting back to the airport drop-off, just follow the signs for Alamo/National (we got the take away full, bring back empty plan, the gas rate was the best we had seen in the area) and it's in the parking garage, you pull in, unpack and the attendant comes and scans the car back in, gives you a receipt and you just walk to the end of the garage and across the street to the airport. So simple, we plan to use them again, as the rate was good and everything happened quickly.