Welcome to the forum.
If you want to be near the beach and near the International airport, then the Central Pacific is definitely the place to be. At the northern extreme you have Puntarenas. This a popular area for Costa Ricans to spend the weekend or holidays and is less Americanized (& less expensive) than Jacó. There are some permanent residents who are Americans. As you go south along the coastal highway there are many beach homes and very small towns until you reach Jacó. Jacó is very well developed, has a very strong tourism market and all the associated amenities. There is a small community of Americans that live year round. To the south of Jacó is Esterillos. This is a nice area and is just now developing, so prices are less than in Jacó, but it is closer to Jacó than Puntarenas is.
As a general point, your rental price (and selling prices) will vary according to 3 main factors:
1) How far to the beach? Beach front is the most expensive, then walking distance. Prices steadily decrease as you go away from the beach, until you hit a plateau that offers coastal views. There prices will rise again but not to the level of beach front.
2) How touristy? As you said, a resort community will be the most expensive, also the amount and type of tourism in the area will affect the price. This is why Jacó is more expensive than Puntarenas, even though they are almost the same distance from San José.
3) In town or out? If you want to be in the middle of everything, you will pay more. I was in Jacó recently and saw a 500m2 lot selling fo $85,000. This is ridiculously expensive for Costa Rica, but not too expensive for a prime location in a prime tourism area like Jacó. For that kind of money you can purchase a 2 acre plot in a less developed area that is a 10 minute drive to Jacó. It all depends on your pocket book and taste.
For you another consideration will be school. I am not sure about bilingual schools near Jacó, although I think there are 1 or 2. If you want to send your children to the best schools, you may wish to consider the Atenas - La Garita area. These are temperate climates between San José and the beach. The kids can go to school during the week and you are less than 1 hour from the beach anytime you want to go.
Good luck and don't hesitate to fire away with more questions.