The Zombie Survival Guide by Max Brooks states that a Katana, if proven to be battle ready, is one of the best hand to hand weapons you can find, If you can that is...

The Guide also states that shotguns should only be used in very tight and close quarter situations. Even if you do manage to hit the head and get a kill the problem of Reloading and capacity comes along. There are however shotguns with magazines such as the SAIGA 12... Picture here.

Get your hands on one of those and a couple magazines and you got yourself a hardcore close range beast of a shotgun.

All other task however, should be taken care by means of Rifle or Sub-Machine gun.

*note* The zombies in the Guide are NOTHING like those in Zmod XD Slow moving, lumbering, but not stupid zombies. I do NOT in anyway believe in "Zombies" i just like the Comedic property of the Book