On the ground, how much you move your stick directly determines how far the surfaces move. The roll spoilers work in tandem with the ailerons to give roll. When doing your control checks you get full deflection of the control surfaces for full stick deflection, so that you can check full, free, and correct movement.
In the air if you command a rate of roll, or a bank angle, the surfaces will move under control of the ELACs and/or SECs to give you the rate of roll or bank angle that you are commanding. There may be extra control surface movements going on that you are unaware of to compensate for turbulence and atmospheric upsets to maintain what you want without you having to constantly correct.
The amount of spoiler movement for a given aileron movement is determined through extensive flight tests to give the smoothest and most effective control. The pilot does not really need to know what the exact relationship is between ailerons and spoilers as long as the aircraft reacts in the way s/he is commanding.
I would have to look up your yaw damper/turn co-ordination question. It will be in the FCOM.