Radisson Hacienda is a newer hotel, walking distance (well, maybe 5-6 blocks) from the main bus station. It's easy to catch the metro bus from there to the Hotel Zone, or just walk downtown to the excellent restaurants and night spots on Yaxchilan just a five-minute walk away. I spent a week and a half there a couple years ago when we went down to Cancun to do our OW/AOW cert dives. If you're a city type, which I am, downtown Cancun beats the Hotel Zone hands down.
Best Day (a big travel agency in Cancun) has a desk in the Raddison (as they do with many other hotels), and they can arrange hotel-to-airport transfers for you. They're amazingly punctual, reliable, and professional. They'll pick you up at the agreed-on time in your reservation and get you off to the airport.