You'll not include yourself as family members. Since it's only your wife, the question no 3 on generic form "how many members, including you, are in the application? The answer is 1 coz it's only your spouse. For instance in my case(on the computer double checking for you)... The answer was 3 coz I have two kids and my wife is third as oversea dependents. So I didn't include myself in the application. I only included myself when we got to no 13 of the form where it asks "current spouse". So your wife is the principal applicant in this form. Hope this explanation helps....