Let's assume you work 20 miles away. God gives you a car and a pair of roller skates. Because you decide to drive to work and not to rollerskate every single time does not mean you don't have a "real" choice.
Does God know which you will choose? I think your choice would be obvious.
Didn't God know 1000yrs ago that you would choose the car? Isn't everything that happens after and a result of, already known?
If it was already known what you were going to do, and it is impossible to do something other than what God knows you will do. I still don't see a choice. God knowing what you will do, and the inability of God to be wrong, forces you to make the choice that was known 1000 yrs before your birth.
Besides, how do you really know that you could have chosen differently? I understand you believe you could, but there is no way of knowing.