Driver door hinge, door doesn't stay open

You are right, they are interchangeable from side to side. The drivers side will have the rollers on the bottom, and the passenger sides are on the top. I have never been able to get those springs to move with the door on the car. I think the easiest way would be to remove the door so you have good access to both ends of the spring. Then, you can pry on one end, and hammer on the other to shift it back into place. There's quite a bit of tension on that spring, so it's not going to move every easily.
Alternatively, after the door is off, you could remove the whole hinge and use a press to move the spring down.