New Zealand is more about natural beauty and diverse scenery than cities. The biggest city on the SI is Christchurch and as you probably know, it's still reeling from last year's earthquakes.

I recommend APEX car rental.

Does your 14-16 days include Sydney? I ask, because there's so much to see and do in NZ, that it's hard to spread two weeks across both islands, let alone include a visit in Australia. In fact, it's quite easy to spend two weeks on one island and still just scratch the surface.

I usually suggest people spend all of their time on the SI because there's just so much to see and do; but because Rotorua is a must see for you, I suggest you fly to Auckland, see what you want on the NI, and then perhaps fly to Queenstown and work your way back up to Christchurch and then depart from there.

Many people choose to make a loop, flying into Christchurch, and then working their way up or down the SI, and then back to Christchurch, but this will involve more driving and thus, require more time.

A possible driving route of the SI: Christchurch-Arthur's Pass-Greymouth-West Coast/Glaciers-Wanaka-Te Anau-Queenstown-Mt Cook-Lake Tekapo-Christchurch. It's a route that includes most of the "must see's" that first time visitors like to include.

It really comes down to time and your personal interests and how much you're willing to drive each day.

Just an FYI - if you (or your daughter) has been to Yellowstone, Rotorua might not live up to expectations. It is the place to go if you're interested in a bit of Maori culture though.

I've been to NZ three times and I "ditto" everything that Melnq8 has said.

APEX--good rental car choice
NI--stay a couple days in Rotorua since that's a "must" for you, but then get yourself down to the SI!
Melnq8's suggested driving route--We've done most of this and I'd certainly recommend it for others.

If you enjoy hiking and think you could take a few days out of your schedule for a hiking trip, I can highly recommend the guided Hollyford Track trip. The scenery on this trip was absolutely amazing; the food in the lodges was delicious; and the guides and staff at the lodges could not have been better.
This was the highlight of our last trip to NZ.

http://www.hollyfordtrack.com/

Thanks for the replies! Because my daughter's company is routing here first to Sydney and then over to Christchurch she thought it would be nice to see Sydney for a day or so,get rid of some jet lag before heading to NZ.
Which of the main towns in the South Island would you be more inclined to spend time in then?
Rotorua looks very touristy-is there other cities on the North Island that you would recommend spending more time in?
I appreciate your tips!

Only two days in Sydney? Really? (But maybe you have been there before.)

Regarding NZ: If your daughter is a marine geologist, she would probably enjoy Kaikoura, on the northeast coast of the South Island, which is close to the Hikurangi Trench, an important deep ocean trench that attracts whales and dolphins. Kaikoura is also a good place for spotting fur seals and sea-going birds. You can go on whale watching tours (this concession is Maori-owned), or go swimming with the Dusky Dolphins. Kaikoura is also very scenic, with high mountains as a backdrop.
http://en.wikipedia.org/wiki/Kaikoura
http://www.teara.govt.nz/en/1966/hikurangi-trench/1

You will probably also enjoy the Marlborough Sounds, which you pass through when traveling on the ferry between Picton (on the South Island) and Wellington (NZ's capital on southern tip of the North Island).
http://lovemarlborough.co.nz/
http://www.railnewzealand.com/pictonchristchurchtrain.html

Yes, Rotorua is very touristy and it smells of sulphur. If you still want to see the geothermal activity, then you can lessen your exposure to the tourist tackiness, by staying outside of town. The first time we visited Rotorua, we stayed in town, the second time we stayed here:
http://www.rotorua.amorahotels.com/
This made all the difference. If you cannot make it to the more remote Eastern Cape of NZ's North Island, then Rotorua is also a great place for learning about Maori culture, though, this too, has been quite commercialized in Rotorua.
This is a good NZ tourism site:
http://www.newzealand.com/int/rotorua/

Are you looking to stay in towns because you do not want to drive around through the countryside and prefer to do day trips from town? If so, I would recommend visiting Dunedin and Queenstown (which, like Rotorua, is also touristy and busy, but sits at the hub of some stunning alpine and lacustrine scenery). The area around Dunedin is rich with coastal scenery and wildlife. Plus, you can do a lot of tours out of Dunedin.
http://www.elmwildlifetours.co.nz/
http://www.wildlife.co.nz/
http://www.penguinplace.co.nz/
http://www.taieri.co.nz/
Jump on, jump off bus:
http://travelheadfirst.com/bottom-bus/passes-prices.html
http://www.coastline-tours.co.nz/penguinexpress.htm
http://www.intercity.co.nz/timetable/lookup/zqn
http://nakedbus.com/nz/bus/


You can also take tours out of Queenstown. Queenstown is not so far from Te Anau & Milford Sound, Lake Wanaka, the Central Otago wine country (around Cromwell and Bannockburn). You can probably get a tour from Queenstown to Lake Tekapo or Mt. Cook, or to the glaciers.
http://www.everythingqueenstown.com/
http://www.realjourneys.co.nz/
http://www.southerndiscoveries.co.nz/getting-to-milford/by-coach-or-bus
http://www.alpinecoachlines.co.nz/WanakaConnexions.html#sched1
http://www.queenstown-vacation.com/queenstown/buscoach/

Wotif is a good site for finding accommodation. If you decide to come to Dunedin, I recommend staying away from the downtown area, better to stay at or near St. Clair Beach.

Nearly forgot, Dunedin is home to the University of Otago, NZ's oldest university (founded in 1869), which has a Marine Studies Program. I don't think it can compare to the programs at Australia's universities, but it is a good one. Dunedin's Aquarium is closed for earthquake proofing.
http://www.otago.ac.nz/marinescience/research/index.html

If you decide to rent a car and drive about, a distance calculator will come in handy:
http://www.accommodationz.co.nz/distances2.html
http://www.aatravel.co.nz/main/td-calculator.php

Thank you for all the help and links-will start looking at them!

Any other places that one must include in a North Island itinerary? We will be on a time crunch of less than two weeks so other than Rotorua where else is where we should spend time up north? thanks-

Wellington is a nice little city, Napier is an interesting art deco town, Coromandel Peninsula, Bay of Plenty, Waitomo for glow worms and black water rafting...

Another recommendation for Wellington, great food: my favourite is Matterhorn, I go there every time I'm in Wellington:

http://www.matterhorn.co.nz/

And there's a great Spanish/Mediterranean place just off Cuba Street: Osteria del Toro.

Also Floritidas http://www.floriditas.co.nz/

Logan Brown always gets good reviews but I went with a large conference group and we all found it a bit disappointing, although the restaurant itself is lovely.

havent been to the north island but i really liked kaikoura north of christchurch..we saw the seals...I think they were seals and it was unbelievably wonderful to see the seal pups cavorting under the waterfall...just go into the visitors centre and theyll direct you ...easy drive to both viewing areas and probably the best out of all the easy access spots to see wildlife

we are more into nature than towns but with the limited time you have i also think the arthurs pass loop to the coast and then back to queenstown would be the best

in saying that though..it is the marlborough sound area that we would return to because OH loves boating and we hope to explore the area a bit more just from the water

abel tasman is incredible but again if time is limited then stick to the earlier recommendations