NO!!!! Not on my watch!!!
From the additional info you provided, definitely sounds like the rotor is being held on by the parking brake shoes. But, like waybomb said, you will have to get the rotor bolt holes lined back up with the hub holes. The parking brake has a "star" adjuster similar to regular drum brakes. (The center of the rotor is the drum.) So you have to screw the adjuster down to allow the brake shoes to move closer together. You can do that with a straight screwdriver, through a lug bolt hole. Once you do that, the rotor should come right off. It is not siezed, or it would not rotate.
You might also try loosening the adjuster for the parking brake cable, which is under the car. That might take enough tension off the parking brake to allow removal of the rotor. Oh, make sure the parking brake is not on.
On the right rear brake, the adjuster wheel should be at approx the one o'clock position as you look at the axle.