When you click the right mouse button while at the main screen, when you click the Jump button, or when you tap the J key, you are taken to this dialog, or one like it.
If you are in North America mode, the dialog is exactly like the one above, which lists the major 100 families of North American birds. As an alternative, you can select a taxonomically ordered list of family names.
In world mode, you are presented the 200 major families, in two windows which you switch between with the right mouse button, or the J key.
In any case, you are taken immediately to the selected family when you double-click the family name or highlight a family name and press Enter.