Cuernavaca is about a 1.5 hour drive (with toll roads) south of the Mexico City.
There are multiple ways of transportation from the airport to the Hacienda: Uber, Taxi, or Rent a Car. It is recommended to pre-pay for TAG (toll-road transponder) for those renting a car. The TAG can be purchased at the airport upon arrival at the 711 or OXXO.
Yes, however it is national flights only and a smaller airport so prices may be more expensive.
Kids are only allowed on Friday at the Welcome Party, and on Sunday at the Brunch. No kids are allowed on Saturday at the Ceremony, Cocktail Hour, and Reception.
No, but it is recommended as its approximately 1-hour faster, safer, and maintained roads.