Welcome to FT lolosmama

NZ economy class has 34" pitch on the 747. These are the nonstop flights from LAX and SFO to AKL (and starting Nov LAX to CHC too). There are also flights using 767 via the pacific islands (makes for a nice free stopover) - pitch in economy is 32". Unfortunately you cant use AA miles on NZ (but United miles accepted!).

For more details I would take a look at the Qantas and Air NZ forums. Lots of friendly and knowledgable folk ready to help.

The best weather is Feb/Mar, so thats a great time to visit. A bonus is school is back so not so much pressure on accom etc. However it is still fairly busy period with lots of foreign tourists, so I would look to book flight awards as early as possible.