Question about steppers

I want to use a stepper to control the quardalift on my shoptask for
the z-axis. I know that 960 oz-in will comfortably turn the
leadscrew, I am planning on reducing it between two and three to one.
That puts my torque requirement between 320-480 oz-in. The leadscrew
is 10tpi. My question is this, if I use a stepper that is 1.8
deg/step, .9 deg/ halfstep, can micro step it to 800 or 1600
steps/rev?
I am trying to compare the torque needed to lift the millhead with
the Speed/Torque curve to see how fast I can make the millhead move,
at least in theory. I am having trouble reading the chart. The chart
for the motor can be found here (it's the N 20 3451):
http://www.clickautomation.com/PDF/items/MAE%20Express%20NEMA%2034%
20Step%20Motors.pdf When the chart lists steps, is that full 1.8
deg, .9 deg, or micro steps? My father is handling all the
electronics for this project; I'm doing the more mechanical side,
though that is a bad reason for why I don't know much about micro
stepping. Our needs overlap in the area of motors, I know how much
torque and what speeds I want everything to move at, he knows what
drivers we're using (Gecko, I think that limits me to what, 10A and
80V?) I'm not dead-set on that particular motor, it's just one I
found that was cheap and had a torque curve.
William