Sounds like a fantastic road trip! If you're history buffs, there will definitely be plenty to take in along the way. Motels do seem to have a bit of a reputation in the States - maybe that's just because we see the seedier ones on TV shows. The first person I asked for help on this was the New York Times' Frugal Traveller, Lucas Peterson. He said that a "nice chain motel" in the US was a bit of an oxymoron - "many are acceptable, but I wouldn't call them nice", he added.
Unfortunately, he didn't reply with any further suggestions, so I asked my contact at Expedia for some well-rated accommodation options.
The majority of her suggestions were from the Residence Inn by Marriott chain - so that seems like it could be a good option for you. For the full list, read the online version of this column at nzherald.co.nz/travel.
I also did some research on the best rated budget hotels/motels and the website Cheapism found that Days Inn and Microtel Inns and Suites were on top. Red Roof Inn and Motel 6 were runners-up - both budget friendly options.
The thing to remember is that even within chains, there can be quite a variety in quality - which you also see in New Zealand. It's always a wise idea to check online reviews before you book - they're brutally honest.
As for routes, since you've got a bit of time, you can really do some sight-seeing. A trip down the east coast to begin could be worthwhile - in Virginia, Richmond is one of the oldest cities in the country, while Jamestown was the first permanent English settlement in the Americas. Further south, the picturesque port towns of Charleston (North Carolina) and Savannah (Georgia) are also well worth a visit.
Otherwise with an inland route, you could soak up all the musical history in Nashville and Memphis, before heading through Alabama to New Orleans. The great thing about the US is there's no shortage of interesting historical sites - I'm sure you'll stumble across some obscure and interesting spots, whichever route you take.
Sue Balderston wrote in with a tip for avoiding deep-vein thrombosis on a long flight - but it's definitely not for those with a fear of needles.
"My doctor prescribes a particular anti-coagulant ... I get two, one for each each way, and inject myself in the stomach before the flight. I was nervous about injecting myself the first time I used it but it was in before I knew it. Easy. I can relax and get all the sleep I want in the window seat without having to think about exercise. Cheap peace of mind."