You would copy everything directly off of your 1099-R into your program, so if the "Taxable amount not determined" box is checked on your 1099-R, do the same in Turbotax and if it is not checked on your 1099-R leave it unchecked in Turbotax.. The item on your 1099-R that determines whether the distribution is taxable or not is the code in Box 7.
