Which is the better out of town location to go to over the weekend with kids (ages 4 and 7): Nuvali or Tagaytay?

I would say Nuvali--travel wise. If you are looking for complete family bonding, you can spend it at Nuvali instead of Tagaytay because travel time is faster and easier (especially if you are driving). Plus, there are lots of things to do at Nuvali with the kids--you can do biking, fish feeding, visit wildlife sanctuary etc. There are also lots of food restaurants available in the area. Nearest hotel to stay if you plan to spend the night would be Microtel South Forbes--clean, cozy and has accommodating staff.