+1. machining rotors vs. replacement is sort of a toss up. Your right one does look nice.... the left one not so much. Some shops won't let you just bring rotors in for machining, instead requiring you to pay them to remove and replace them. Beyond that there may or may not be enough depth to the rotor to machine, and even if there is doing so takes some of the thickness out of the rotor increasing the chances it will warp later.

You can always ask for a machining estimate somewhere and check the details. They'll let you know the cost and if the rotors can be machined. Check the price of new rotors as well..... when I did mine it was about $20-30/rotor to machine, or $45/side new.

As to doing it yourself it's totally doable. The catch with the rear brakes is the piston needs to be compressed and turned to retract for the new pads. There are several compression tools around you can use, check with your local auto parts store to see if they rent one out. Otherwise you're stuck with the needle nose plier method which is a PITA. Beyond a compression tool you need a large allen socket for the slide bolts (can't remember the size of the top of my head).