You mean the Brake Rotor (I assume not Distributor Rotor). For the Brake rotor take off the wheel and unbolt the brake caliper. There are 2 screws holding on the rotor, use an impact driver to remove them, DON'T USE A SCREWDRIVER, you will strip them and make it a bitch to get them out again. The huge nut you speak of is the axel nut, it holds on the axel, not the rotor.