How can I prevent tabbing to a UserControl?
Use the KeyboardNavigation.TabNavigation Attached Property with KeyboardNavigationMode.None on your container control.
KeyboardNavigation.TabNavigation="None"
You can bind IsTabStop on the child controls to IsTabStop on the UserControl.
That way, you only have to set it once.
You could write an attached property that you would set in the top element.
That attached property would recursively set IsTabStop to false in all the child elements.
Let me know if you need any help getting this to work.