I would highly recommend that everyone should go to NZ if they have the time and opportunity. It is a beautiful country. If you go, you should plan on doing some physical activities (hiking, whitewater rafting, etc.) as this is a great way to see some of the country.
My favorite activities were the hikes, the glacier and the time on the farm. The hikes were a great way to meet other people and see a beautiful area. The glacier hike was something I did not have planned, but did this after the whitewater rafting trip was cancelled. The time on the farm was relaxing and it gave me an opportunity to meet some very nice people and learn a bit more about the country.
Stayed in a couple of beds and breakfast places and those were all nice. Also stayed at Novotel Hotel and this was a very nice and reasonable hotel (Queenstown, Christchurch and Wellington). All of them were located in a great area near a number of other things.
Driving was a bit of an experience, and I'm not sure how necessary it is. There are a number of buses (particularly on the South Island) and also trains, shuttles, cabs, planes, etc.
In order to encourage someone to go to New Zealand, the first person to plan a trip can contact me and I will send them the $14NZ that I had left when I got home. This may not seem like much, but my last night in Auckland, I found a bar that had $4NZ gin and tonics (turns out it was student night, but I must have looked like an old student) and another one that had $5 bottle beer and free food for happy hour, which lasted until 9 PM.