There should be (2) 14mm bolts holding the Caliper in place. Simply remove those and swing the caliper up and out of the way and the rotor should slide off with ease.
Good Luck and...
First remove the tire and brakes, the hub just slides over the lug bolts that hold the rim on, so take it off and replace it. Always put new brake pads when replacing a rotor.
I just did this this morning. Once you remove the caliper and brake pad frame, you have to beat the rotor with a heavy hammer. Work around methodically in a circle and avoid hitting the threads on...
Front ones only need the brake assy. taken off to remove the hub. The rear ones require a bit more. If the hub is worn down considerably there will be a small ridge inside. You will need to loosen...