I like Hotel Plaza Mayor. They are clean, friendly, bi-lingual and in the city center. I have had all of my family stay at that hotel and they loved it. Plus, it is not too expensive..
www.h-plazamayor.com They are on Calle Atocha 2 or send an email; info@h-plazamayor.com
You are getting in early enough to take the metro into town and not get robbed by the taxi drivers. If you are not carring much..go for the metro for it is in the airport and you can pick up metro maps at the info desk. enjoy your time.