Beautiful but not for little kids
This place is expensive - they do overcharge. but the people are so nice and everything is very clean. the pool is fabulous. However, the kids club is for kids aged 4 to 12 and from 10am to 12am and then 2pm to 4pm. But, when my daughter went to the kids club she was the only kid in there - maybe it was a down week, but there weren't a ton of other kids to play with.
Also, the tours are not geared for kids. You can take your kids - I think they would have let my 2 year do the zip line...but again, they are not designed with kids in mind and you won't have too much fun on the tours if you bring young children. The jungle tour (Carara) was basically bird watching which was entirely boring for my 6 and under crowd. The boat ride to see birds and crocodiles was fun for them and 'relatively' safe (you need to keep a hold on the little ones as there are no seat belts and lower sides on the boats.)
Also - if you need a sitter - they provide VERY qualified (cpr, etc.) sitters, but 24 hours notice is not enough, even though they told us it was. If you think you might even want a sitter, book them WAY IN ADVANCE and then cancel if you have to.
By the way - the pool is great. there is a baby pool that is about 18 inches deep. the big pool is 4' all over with lots of places to enter/exit that have WIDE steps. A good place for little ones to hang out too. But, if you don't have kids that are good swimmers, its hard for you/them to swim here because you have to hold them up - as its so deep.
The taxi ride (we used their service -CRT) was as comfortable as it gets, but is still a grueling 2 hour ride, especially if you have just flown a long way into San Jose. It makes for a VERY long day.