Depends on the experience you are looking for, Alberti...
But if it were me, I would stay in Playa del Carmen or Tulum.
If you want a more luxurious resort experience, like Raymond suggests, you can check out Mayakoba, or Gran Velas, just a little north of Playa. I know of some nice resorts also in Puerto Morelos, but unfortunately I cannot point you to a specific property.
October to mid November is a great time to visit, as the sea is most calm, beaches are clean, and not a whole lot of people travelling into the Mayan Riviera.
Playa is nice because it lends itself to walk around. There is a small hotel called La Semilla, more of a Bohemian vibe, close to 5th avenue and 38th St, close to the beach, restaurants, and bars. One favorite of mine is Be Playa as well.
Be sure to venture out south into the many cenotes close to Playa, Jardin del Eden is one, within a 10 minute drive, and Xpuha beach, halfway down to Tulum.
Have fun and keep us posted!
Feel free to PM me for other pointers.