I agree with the previous post... oerlikon, especially the neu-oerlikon area is very child friendly and there is even a community center with an english speaking baby play group etc. Also, you will find that the price of a good apartment here is significantly lower than in the center of town. I assume that you you also want a lift and underground parking if you have kids... tough to find in Zurich center. Let me know if you need more info.

Good luck.