It's good to see my government finally getting serious about the real threats that face Americans today:
The CDC's preparedness tips for surviving the zombocalypse.
Of course, being a government organization they don't include weapons in the emergency kit, but that's to be expected. In the hysterical days after September 11, government-endorsed emergency preparedness lists pointedly refused to include even a Swiss Army Knife or multitool, presumably either for political reasons or out of simple fear of liability. Either way, it seems unlikely Uncle Sam will make suggestions on an end-of-the-world rifle any time soon.
So while the CDC list covers the really important essentials like duct tape and a copy of your birth certificate*, be sure to supplement with an appropriate battery of anti-zombie weapons. Your best options, in this blogger's humble opinion, are an AR-15 and a 9mm glocklike pistol--or, if you don't anticipate needing to fight humans, a semiautomatic rifle and pistol chambered in .22 magnum, fed from removable magazines if at all possible**. "Stopping power" is much less meaningful when only headshots count, and you'll be very happy with the light weight and compactness of your ammo when the horror-movie addicts you bug out with all give themselves hernias schlepping around their 12 gauge shotgun shells.
Note that many zombie wonks prefer to eschew guns in favor of melee weapons, because "blades don't need reloading". These specialists are a great asset to your group, and should be encouraged to travel with you. After they engage a threat, their delicious brains will provide the diversion your party needs to slip away from the feasting zombies.
[* - You won't be admitted to the Safe Zone if they think you were born in Kenya.]
[** - Finding such a .22 WMR pistol can be a trick. A revolver is an acceptable substitute if you're going the .22 mag route. It's a last-resort weapon anyway. Or just pair a 9mm pistol with your rimfire rifle.]