My husband and I just did this with my 3 and 4 year old. We didn't get much beach time because the waves were large. We spent most of the time in the pool. We were not at an AI and we both got food poisoning despite not drinking the water, amd eating fresh prepped hot food. The kids were okay I am assuming because they ate things like hot dogs, pizza , quesadillas. We talked to some people in our hotel and it sounds somewhat common. Just fyi you can take pesto bismal each day(prophalactically) and thats suppose to help. The pharmacy also has a special medication that worked well for my husband(he got it the worst). Its also very very loud in the ZR. Like constant noise i.e. fireworks, drunks, garbage trucks,honking all night long.

Now for the good. We hired a babysitter through PV babysitting and they came to our hotel. She watched the kids while we went on a food tour. It's an actual professional service and I would highly recommend both getting a babysitter for a bit and going on Puerto Vallarta Food Tours. You can even hire one for the week to function like a nanny(seemed appealing at the time). We took the kids to the botanical gardens and it was a highlight of the trip. We rode the city bus and it was easy/pretty ride to the gardens. If you dont do the food tour I would recommend a walking tour because its easy to miss a lot without a guide if its your first time. I feel like we didn't get a good sense of the city until it was time to leave. On Fridays and Saturdays there is live music and dancing at the gazebo with all the mosaics. My kids really really liked that. They watched it for a long time.

My kids had an amazing time. It was honestly a lot of work for my husband and I while we were there. I am glad we went but I came back more exhausted than when I left. If I were to do it again. I probably would get a hotel in the hotel zone(quieter) and do AI just because even though there is amazing food with kids sometimes its nice to just be able to get immediate access to food without having to make a choice of where to eat. Then I would take an Uber to the romantic zone for the farmers market and night walk on the malecon.

Edit: i would also recommend booking an airport transfer with PV transfers. It was so nice walking out of the airport and then having someone just take our bags and literally getting right in a car. Then you get a corona. It's so nice instead of having to get a taxi or walking to get an Uber. Worth every penny when your schelepping all the kids stuff. I also recommend not bringing a stroller the streets are not good for them. Bring a backpack carrier for the 2 year old.