Since it's a family trip, Hidden Worlds might be a nice option. You could book yourself on a 2 tank cenote dive - Dos Ojos and Bat Cave (see if you can get Jeff as your guide, but make sure it's Jeff who's originally from Texas). The rest of the group could do a snorkel tour, which are done at different cenotes on the Hidden Worlds property, or try one of their new attractions - Zipline or the Skycycle.
Unless of course you are looking for some time off on your own, then get your own guide and leave the family at the resort.
I've done Hidden Worlds and they were good for our first time. I've also been with guides and enjoyed the guided dives we did with Dennis best. If he's not available I'm sure he would recommend someone else for you.