Well just knowing that there are may off-brand sub-par quality drilled/slotted rotors that will warp just by you looking at them the wrong way, I would start there. EBC makes good stuff, though they can be somewhat harsh on rotors. EBC + subpar quality rotors....I think you get the point.
Just the regular Brembo/OEM blank vented (not drilled/slotted) rotors work the best, and last the longest. From there, there are many pad choices to pick from. Might also be a good idea to lift the car and check the suspension just in case though, however normally a worn suspension on these cars will result in the '55mph shimmy'.