I'm sure the following has been addressed, but..
1) Water is your friend, how long can you survive w/o water versus food........
2) Gun: Well, we've some truly devastating, overwhelming disasters as of late. Note once have I seen reference to the need. If the s*&t hits the fan, we are typically all in it together. Plus, usually it's gun safety ignorance that causes harm (to oneself).
3) Driving: good luck. If in an urban area (me....SoCal), ain't going to happen. Me and 20 million other folks......., If in country side more than likely you have what you need on the spot. Plus....driving with the masses is more likely more risky than staying put.
Probably best advise i can throw (CERT, ski patrol, nurse as far as training here), keep all emergency stuff out of structures so you can get to it if structures collapse. If you lucky enough to have a dedicated rig ready to go, keep all that stuff in it. May not go anywhere, but at least the rig might be available when you finally emerge from initial devistation. Nugget: Keep a set of work/heavy boots & head lamp next to bed!