You all epically fail. Possibly the best weapon to take out a zombie is with a standard Hunting rifle.
The bolt action rifle is a product of the nineteenth century; these weapons are regarded as obsolete now. Why use a hunting rifle when you can own a sub-machine gun? Such arrogance is simply unfounded, its roots based in techno-chauvinism and the absence of practical expense. A well made, expertly used bolt - or lever action rifle offers defense against the living dead as good if not better than the latest military hardware. A rifle's single shot capability forces the user to make each round count, increasing the chance to hit it in the head. It even eliminates the possibility of "rock and rolling" of switching to automatic, and therefore conserving ammunition. A third reason is the easiness of cleaning and to operate a civilian rifle. They are not something to be overlook about this reason; they are easier than most military hardware to clean. Manufactures know that if they are to complex sales will plummet. A fourth and final reason is the availability of the ammunition. As there are more civilian gun shops in the world than army surplus stores in the United States, (Ironically no where else in the world has as many civilian guns shops, so if you live anywhere else use a sub machinegun, which uses a 9mm round.) It will be much easier to obtain ammunition for a hunting rifle than a 5.55 NATO round. This will be critical in order to survive.
For a melee weapon one of the best choices is actually a crow bar. With the titanium alloy, its light weight and provides crushing and cutting power. It also allows for uses outside of combat like opening a locked door.
People who say they will choose a katana are probably 10 year olds who imagine themselves as the heroic figure going out alone and stopping the world. This would get themselves killed as once one zombie moans, it triggers a chain reaction of continues zombies. And the 10 year old wouldn't even be trained, nor have the muscle mass to decapitate a zombie with it. It takes years to master the katana. The chainsaw or any other sort of power tool would also be a bad choice because of fuel; one slip with the chain saw could also cut you, as easily as it cuts a zombie.
Learning a hand to hand combat more for escaping grasp, and then inflicting damage because, it is necessary to escape a zombie?s grasp. So always be prepared and train with everything EVERY day. Clean and take apart the gun every day, during the night and during the day, blindfolded and backwards, know everything in and out and how to fight with it.
THEN you may live during a class 3 or 4 outbreak.