Mexico - Family-friendly resorts in Mexico?

No real preference in terms of where (Gulf, Pacific, Baja, wherever), but want some suggestions and experiences in terms of a good family getaway. I'm initially thinking all-inclusive resort for 4 nights or so, but would entertain other ideas.

My 2 daughters are 6 (almost 7) and 4 1/2. Both love swimming, biking, beaches, animals/wildlife. Wife is pretty open to most activities, excluding most extreme sport type things (not a fan of ziplines and bungee jumping, for instance).

We don't have money to burn, but if I can use (or earn!) Marriott or Hilton points, all the better.

Not sure when we'd go, but probably sometime in the fall or winter. Maybe yank the kids out of school for a week :D

Did a search of the Mexico forum, but not much of use. Thanks!

A friend of mine is staying at an all inclusive (Villa del Palmar, north of Cancún and Puerto Juarez, south of Puerto Morelos,) with her daughter; we expect to have dinner with her Sunday in Cancún and I will ask her about this newish all inclusive resort.

Some resorts cater to kids with lots of activities - and in Mexico, the month of November is referred to often as "Novi-hambre" (Nov-hunger) because the tourists are markedly absent, prices are lower, and it's of course less crowded. (Hint: Dec 15 or thereabouts, the Secretaría de Turismo newly-authorized, higher and also high-season rates go into effect.)

Thanks for the tip re: Novi-hambre! I'll keep that one in mind.