I would have to agree that New Zealand looks like the most promising location to be if the world turned pear shaped. Consider the following:
1) New Zealand is geographically isolated from the rest of the world, making a nuclear attack seem unnecessary and difficult. The country is broken
into three main islands with thousands of smaller islands. The three main islands stretch a long way making the country very spread out (to drive from
Wellington to the top of the Kaitia, on just the north island takes about 24hours)
2) New Zealand is large enough and has enough resources (including gold, oil, iron, and fresh water, forestry) to sustain itself COMPLETELY. There are
the means for self-sustained energy, include wind, geothermal energy, major rivers and sea currents for potential aqua turbines. NZ currently
possesses the technology to make these things happen.
3) New Zealand’s landscape is some of the most diverse in the world with mountains reaching 14,000ft, deserts, lakes and the most fertile soil in
the world. Similarly the climate is diverse with low lying areas in the south getting snow, and temperatures in the far north that never really get
below 12.c in winter.
4) NZ has 64,000,000 sheep, 29,000,000 cattle and three million people, millions of acres of orchards, some of the best fishing in the world.
5) It is the only place in the world that has no deadly animals (I believe Ireland, the only other country with no snakes, has a poisonous spider).
6) NZ houses some massive caverns and underground cave networks stretching kilometers that could house thousands of people need be.
However, we do have a problem with those pesky Orcs, a few bad elves and the occasional bandit horde of Rohans.