It's normal to have somewhat of a lip on the edge of the rotor, yes. If the lip is too deep you may want to measure the rotor thickness. MB doesn't recommend machining the rotors. If the thickness is still acceptable just reuse the rotors and don't worry about machining.

The rear about the same as the front, yes. Just 2 bolts holding the rear caliper to the bracket, takes a 13mm wrench to remove the 2 bolts.

Gilly