Squealing brakes while stopping

[Dardas]

1 of the few problems i have with my car is the brakes. I had abs brake work done when i purchased my 03 ZX3 focus over a year ago and they seemed to work fine but around the last 6 months or so, about 50% of the time when i am coming to a stop there will be a squealing noise when under 15mph. I can tell by looking at the car the rear drums are rusted to hell, but i am not sure if thats the main priority to fix right now, or if its the front brakes. And if so, what is causing the squealing? rotors, pads, drums??

[Sponsor]