2000 Acura Integra frozen retaining screws in rear rotors

Those screws are impact driven on, meaning you will need an impact driver to remove them. That or you can use a punch and a hammer. Make a decent indentation with your center punch, then use that indent to work the screw off with the punch/hammer. If they are truely rusted in there, you will have to heat them up and try again or just drill them out.