$44, did you get ceramics?
I wouldn't bother with the rust. The important parts shouldn't have any. Is the brake pad wear somewhat even between the sides? If not, you might have something sticking.
I can't recall if any of my vehicles have squealers on the pads, but it doesn't matter as I examine pad thickness every time I rotate tires. I'll probably never go through the pads on the Prius, and might do 1 replacement on other vehicles in the lifetime of driving them due to avoidance of brake use.
As long as you have enough pad material left to prevent metal to metal contact, and you don't have squealers, the worn pads wouldn't cause the noise. Maybe your pads need some anti-squeal compound, or perhaps the moving bits need some grease so they slide more freely.
Front wheel drive cars will be more difficult to spin the wheel due to the drag of the axle and differential. The non-driven wheels should spin relatively more freely. I know my Prius front wheels are very difficult to turn by hand.
