Chevrolet: 1999 Malibu ABS, abs system, brake switch

Question
Harold,
  This Malibu has a VIN of 1G1ND52T4X6138252. The question I have is a bit complicated. When I got the car, the brake pedal had a pulsation like the drums were out of round. I felt nothing in the steering wheel. It needed new tires and I had them installed. The problem seemed to get worse. I took a trip and used the cruise control. When slowing down (braking to turn off the cruise) from 75 MPH, the whole car shook violently including the steering wheel.
  Is the ABS system somehow connected to the cruise? The longer I drive it without the cruise on, the better the brake "feel" becomes. The pedal still pulsates mildly but I'm confused. I have a degree in Automotive Technology from 1974 but this new technology has me scratching my head.
 NO rush. The car stops and no one is going to get hurt. Just when you have a chance, any ideas would be appreciated. Thank you for your time.
Skip

Answer
No the cruise and the ABS are not connected other than the brake switch which turns the cruise off and also sends a signal to the ABS module telling it that you are stepping on the brakes.
Sounds to me like you just have a good old fashioned brake pulsation, and it sounds like it is a problem with the front rotors.