I can tell you some of the answer. Meet the Press is fed live to all the NBC stations. Most of it, if not all of it, is live at 9AM Eastern Time. Your station might receive a 10AM feed of Meet the Press. The 10AM feed is taped from the 9AM live broadcast. (NOTE: It's not actually tape they use in NBC-Master Control, it's actually hard drives.) There might be portions that are taped, but most of it is live. Also, you may watch Meet the Press again; Sunday night, early Monday morning (check your local listings.) Most stations air what's called "Meet the Press All Nite" around 3.30ish in the AM. "Meet the Press All Nite" is a recorded feed from the 9AM showing.
I'm sorry I can't help you with the other shows, because I only work for an NBC station in their master control.
NBC affiliate, Master Control Operator