Brother, in the generic form for your wife's Education/Occupation Detail, you need to fill her current as well as intended occupation. Now clear?
Elementary/ Primary school = 5
Secondary/ High school = 7
University/ College = 4
Trade school/ other post secondary school = 0
Ignore 'Separation Declaration for Minors Travelling to Canada [IMM 5604]. You don't need to fill up 'Separation Declaration for Minors Travelling to Canada [IMM 5604]'.
Thank You man! everything is clear. But I guess there is no way to write her NOC code anywhere! her occupation is Engineer and intended occupation will also be Engineer. I will also write my occupation Engineer as my designation is Engineer. My code will be 2281