If you are not paying any "income" tax on this tax return, a Traditional IRA is not saving you any money. But whenever you withdraw the Traditional, the withdrawal will be taxable.
If you contribute to a Roth, as I mentioned before, the Saver's credit will offset any "income" tax, so you will have the same result on this tax return ($0 of "income" tax). BUT whenever you withdraw the Roth, it will NOT be taxable (if you withdraw it before certain timeframes, the "earnings" could be taxable, but if it is a "qualified" distribution it will be completely tax free).
