I agree with the last few shouts for the 3E Adventure Boxed set. Its good, simple, comes with a nice lil map. Everything goes along smoothly, and the kids will have fun with it. Next, toss a PHB into the mix for the players so they can create their own diverse pcs, and get your buddy a DMG so he can read about gamemastering in that. The 2E dmg was completely useless and I never learned anything from it, except you had to have it to generate treasure, but the 3E dmg has most everything I can think of. It has the magic items, all of the "living in fantasy" stuff, travelling, how to set up adventure lines and plot hooks, as well as simple generation stuff that novices will not know how to do, like create villages and whatnot. It will be great building blocks.
~~Brandon