About how much will it cost to fix abs system? Or can I disable it?

You can not disable the ABS sensors, sounds like you have more then the sensors being bad, sounds like the rotor maybe locked on one of the brakes, Sensors are about $35.00 each. Sometimes cleaning them will correct the problem. Your bearing may not be good causing a gap in the wheel thus tripping the sensor. It would be around $200.00 per sensor to replace depending on what part of the county you live in.