Your age determines only whether the payments are required to appear as pension and annuity income (Form 1040 line 16 or Form 1040A line 12) or as wages on (Form 1040 or 1040A line 7. If you are considered retirement age by your company then you are.
It has nothing to do with determining the taxable amount of this income. Box 2a of the Form 1099-R will normally show the taxable amount. A normal pension distribution also shows a code 7, in box 7 as well.
