If the family is Active, go to the "Families" tab and then pull up the family in the drop down that you want to delete.
If the Family is Recruit, Wait List, Inactive, or Exited, go to "Families" tab, and then to Non-Actives on the left. Pull up the correct List and select the family you want to delete.
From the Family Data page, on the left hand side, click on "Family Home".
Once you are on the Family Home page, you will see the option to delete at the bottom of the left hand menu.