You should file jointly, as
it is the most beneficial filing status for married taxpayers. The fact that
your wife has small income will help your income (while file jointly) to be
reduced by 'joint' deductions, which may increase your refund/ lower your tax
liability. For a detailed comparison of both
statuses, please click here.
As to the scholarship, it will be considered taxable income if it exceeds the tuition and other qualified expenses; otherwise it is not taxable. TurboTax will calculate it for you, once form 1098-T is entered, along with scholarship amount and education expenses.
And your last question - scholarship is considered unearned income.