New Zealand Flight

Scheduling the journey as a stopover on the west coast would make for a more comfortable trip and might actually be cheaper, depending on your specific dates, etc. Could fly from Boston to either LA or SF, spend the night, then depart fresh the next day for the non-stop to Auckland. Thing is, most of the west coast flights depart between 8 PM and 11 PM so you'd need to either extend your overnight hotel stay or find some other way to pass the time between hotel checkout and the check-in for your flight. We've done it that way a few times and it's worked well for us.
My suggestion would be to book the long flight to Auckland on Air New Zealand if possible. Very nice airline, and last I checked their economy seats offer a bit more pitch (legroom) than most of the other carriers. Their Premium Economy is the equivalent of Business Class on United or Delta...if you can afford the upgrade. First checked bag is free.
Most flights arrive in Auckland very early, ie 5 AM to 8 AM, and collecting a rental car and getting on your way is really pretty easy. They used to offer Day Rooms where you could shower and generally freshen up before you left the airport, but am not sure if they still do that.
Remember that you'll be driving on the left, but once you get the hang of it the driving there is pretty mellow...especially outside of Auckland.

Looks like they do still offer showers at AKL : http://www.aucklandairport.co.nz/AirportInformation/International-terminal/Terminal-services-and-facilities/Showers-and-toiletries.aspx

It's a great way to freshen up after the long overnight flight.

You won't have too many choices for layovers. One stop in LA or San Fransisco, or two stops with the LAX/SFO and Pape'ete (PPT). You do get in early so that first day is a long one.

Personally I'd rather do the the 13 hour flight from LAX to Auckland than two stops. When we traveled to New Zealand we did an open jaw into Nelson (south island) and depart from Auckland. Or flight from LAX arrived in Auckland and we went through immigration and customs there then transferred to the domestic terminal for the flight to Nelson. This help burn some time that first day since you arrive so early and then we weren't back tracking across the north island to depart. We flew Air New Zealand.

DJ

Another west coast possibility is Vancouver, BC, although as I recall their non-stop flights don't operate every day of the week. Still, with the current favorable exchange rate it might be worth a look since you'd be paying in Canadian $.

We wanted to fly into Australia this year and take a cruise over to and around New Zealand. We found the open jaw flight alone to be very expensive.
We ended up flying to Copenhagen on Norwegian Air Shuttle and took a 9 day cruise around Scandinavia--for about the same cost as just the airfare to New Zealand.
You can fly Boston to Houston and transfer to a 14 hour non-stop flight to Auckland on Air New Zealand. Or, you can
fly into Los Angeles and go non-stop from there.
Another option would be to fly into Honolulu and spend a couple of days. Then fly on over to New Zealand on either Hawaiian Airlines or Air New Zealand--whichever is less expensive.

If you plan to visit the South Island then looking at open jaw possibilities with ANZ is a good idea. Most of the cities on the South Island are non-stop from Auckland, so after a short layover there you could easily continue on to Queenstown, Christchurch, etc.

Ellen,

On that route, my preference would be to stop in Honolulu for a few days, and then continue on to Auckland. The most tiring part will be the 13 hour (or so) flight from Boston to Honolulu. The segment from Hawaii to Auckland will be about 9 hours or so. Air New Zealand has flights with layovers in either L.A. or San Francisco, and the shortest travel time is about 20 hours. There are lots of different ways this could be arranged using a variety of airlines. You'll have to do some number crunching to determine the best cost and least tiring route.

On that particular route, there are no easy answers. The stopover in Hawaii would be the best option (IMO) as it breaks up the journey and provides a great place to "recuperate" for a few days, sitting by the pool with some of those drinks with the little umbrellas. Stopovers at Vancouver, Seattle, San Francisco or L.A. should also be easy to configure.

For that route, I would go with air New Zealand. Although I love travelling, I hate flying with a vengeance and there are only a handful of airlines I am happy to fly with. Air new Zealand is one of my favourites.

I agree with Ken. Honolulu is about the best place to spend a day on the way to or from New Zealand. Check out options with Hawiian Airlines.

My second choice would be Los Angeles so you can have a non-stop flight the rest of the way.

Another option: stop over in Seattle or Honolulu. We already have tickets from Seattle to Auckland with changing planes in Honolulu. Hawaiian Airlines. $ 900 per ticket. But of course you are flying from Boston. You can also look at your options flying east (via Dubai? Singapore?).

Starting soon (December I think) you can also fly direct from Houston to AKL on Air NZ.

Also, if you are want to save some $, it's almost always cheaper to fly LAX to SYD (or Brisbane) and then back to NZ (you can fly to Auckland, wellington, Christchurch or Queenstown from Sydney) on a single fare. More airlines flying into Sydney means greater price competition. Virgin Australia is a good option for this. Qantas fly from Dallas to Sydney direct on an A380 (as well as LAX).

My experience is that US based airlines are pretty basic in comparison with the service you get on Qantas, Virgin or Air NZ.

I'm not a big fan of layovers to break up a flight. I'd rather just get it over and done with and keep moving to get where you want to be. Also, less dealing with airports, transport, hotels, one lot of jet lag etc. Unless you particularly want to visit LA or Hawaii, in which case just make sure it's long enough to enjoy it.