Presently on unemployment - for all of 2012.
Chose no withholding tax as option for weekly payout.
My yearly expenses ( based on home mortgage / medical expenses etc.. ) greatly out way all income / tax payback about...
When doing 2012 tax return do I have to state the amount of tax that would have been needed to pay back even though I will not need to pay back since expenses wash out need for tax payback??

Tax is payable on taxable income, for tax purposes when your income is less than zero it is called a loss. As you are not carrying on a business this concept is of no use to you.

Depending upon where you live mortgage interest may be deducted against income as may certain other expenses but if you expenses exceed your income where did you get the money, the tax man may want to know