Goto the person in the tree view of who you want the home person to be.
Click EDIT -> PERSON - > SET AS HOME PERSON
Martin - thanks for that but I just can't find which Edit button and Person and Set as Home
can you help an idiot and be more specific about were I find these thing? Many many thanks
At the top of the 'Family Tree Builder' screen, you should see an array of icons.
Click on the 'Tree' icon to ensure that we are both looking at the same screen.
Move around the tree until you can see the person you would like as your 'home' person.
At the bottom right of that persons window, you should see two buttons 'Edit' and 'Photos'
Click the EDIT button and a pop up menu should appear.
Move the mouse down to the second option :- PERSON and another menu should appear.
From that menu click on SET AS HOME PERSON
Now, whenever you click on HOME from the array of icons across the top, it will display your home person, in my case, ME! :-)