Hey kkr,
I didn't had any interview but they have asked the same thing to submit all my marriage ceremony photos & post marriage photo's as well & documents that establish my relation with my spouse... So i did the the same submitted all ceremony pics & in additions ceremony DVD's as well, with that my insurance, my medical policies, marriage certificate (which i did submitted earlier also) etc whatever documents that I can gather having my spouse name as nominee on it... In interview inspite of communication skills they might also check that are you ready to face challenges in the early years of the immigration to Canada...
Don't worry & be confident everything is going to be just fine...
Best of luck..
God bless
Regards
Arun