If you are filing as Married, Filing Separately and your wife has no U.S.income and no U.S.return, then, for NY tax purposes, her AGI is "$0".
The answer for her "dependents" is the same - "0".
NY is asking this question to make sure you aren't using "separate filing status" to get deductions and credits you (or your wife) don't qualify for, either from NY or another state. Since your wife isn't subject to U.S. (or NY) taxes and you are filing separately, her information is not relevant to your NY tax return.
