The spouse's ability to work will depend on a number of factors, such as how remote work is compensated from the company and the actual visas you get.
The kids are at a perfect age to be exposed to another language. You will likely put them in a private school, as that is the done thing amongst the Mexican middle and upper classes in all but a handful of cities. But the costs may not be any more than school lists and fees that you get in the US. I knew one family that chose a school for good reasons, were happy with the costs, but still shocked when there was a school trip planned to Europe. For elementary students.
A lot of the success will depend on the spouse's attitude (which may be affected by whether or not they can work). Often in ex pat situations, the worker loves it and the spouse just doesn't find their groove, which will impact the children, as well. If both you and the spouse embrace the experience, the kids will likely follow suit, eventually. There is a large, active ex pat community in Puerto Vallarta, you can read their blogs and ask questions in their forums for local specifics.
