I've read the zombie survival guide, and while I haven't necessarily started stockpiling arms and watching the news for signs of outbreak cover-ups, I've definitely made myself familiar with what makes a good anti-zombie weapon. Accuracy and silence.
As almost any non-head shot will result in a maimed zombie at best, it is important to use something that can reliably hit the target.
And silence. The advise against chainsaws seems good. The heavy gas powered weapon can quickly make mince meat of any immediate zombies, the noise is guaranteed to alert any nearby zombies to your location.
Fire arms tend to have some of those noise troubles as well- the much lauded AK-47 is a noisy weapon after all.
Here are some cake toppers I made for couples that know how important silence is during a zombie outbreak.
The crossbow is an excellent weapon- nearly silent, but quite accurate (at least if you've practiced enough with one).
And melee weapons tend to work well. A sword is a classic so long as you can find a quality blade. On the other hand, we have drumsticks. But hey- a weapon you're familiar with is often better than a superior weapon you've no experience with.