sounds like he meant that if they were drum brakes on the rear, he'd have to take the drum housing apart to get to the shoes. So what he means is, he just takes the wheel off, and has full access to the discs, pads and calipers (the braking system for that wheel)-nice and easy and simple to fix if ther eis an issue
i'd be fairly sure you will be fine driving...lets put it this way, i was driving around with no pads left on my brakes-metal to metal...this is bad...so i am sure you will be fine if its just a little squeel! The rear brakes dont do much anyway when driving-they come on under harder breaking, extra load in the car or handbrake, generally the braking is done at the front wheels.
That's the one, no drum indeed! He won't have a chance to look until sunday, but school is within walking distance, so I only really go out to the supermarket and other places if the weather is nice (hahaha