You get to deduct either all your itemized deductions or the standard deduction whichever is more.
For 2014 the standard deduction amounts are:
Single 6,200 + 1,550 for 65 and over
HOH 9,100 + 1,550 for 65 and over
Joint 12,400 + 1,200 for each 65 and over
Married filing Separate 6,200 + 1,200 for 65 and over
