Changing front rotors and pads

Im trying to replace my rotors and pads. Im doing this cuz I just got it and it shakes at high breaking speeds so the rotors obviously are warped and need to be replaced. I have everything disassembled in my garage all the way down to the hub. The problem is when I started reinstalling everything the bracket that mounts the caliper to the steering nuckle rubs against the rotor and prevents it from spinning properly. How can I prevent this from happening? Also after further inspection the rotors spin much the way an unbalanced tire would. Do u think I did not get them on properly or that the hub is warped too and that is the root of my problem?