I don't know how can I proove that but I know my secret question and answer before they changed it
I've been through this situation before, they will ask you for any folders you may have created in your account, if none they will ask something unique your hotmail account has that will prove it's yours.

You should always give the "wrong answers" that way people cannot socially engineer their way into your account
I forget the RIGHT answer, how am I suppose to remember a wrong one?