thanks to everyone recommendations where to stay on drive from sydney to brisbane they were very useful. we have decided to take 4 days travel there, and get the train back to sydney. Next question any recommendations for some where north of brisbane (not to far) to stay for one night. Now the are we being paranoid/patronising bit. On looking at various motels en route some say, en-suite rooms, many do not say this, do most motels have en-suite facilities or are shared bathrooms the norm. My wife is a little concerned about this.

Motels will have en-suite rooms but many B&Bs have shared facilities. Most old country pubs will have shared facilities.

I have no idea how far not too far is but if you don't want the Sunshine Coast then why not try Maleny, Palmwoods or Mapleton. These are in the hills and well set up for tourists.

If you want to stay on the coast, Mooloolaba and Maroochydore are both good places to stay - lots of accommodation and restaurants.
I think we take it for granted that all motels will have en suite bathrooms. The more old fashioned country pubs and B&Bs may have shared facilities. I understand how your wife feels - who wants to go wandering down the hallway in the middle of the night.

As both AlanJG and Marg have posted, the sunshine coast has lots to offer.

having a range of accommodation facilities and a gorgeous range of scenery to go along with it. from Mountains to the coast - your choice really.

One night I wouldn't venture too far north, just so you'll have more time to absorb the space/place you are in.

As for the bathroom situation, again as both AlanJG and Marg have posted. Motels/resorts all have in room/ensuite facilities, the only times that it wouldn't hurt to double check is in the B&B and historic pub sector of the market. some B&B's do have ensuite facilities - but this is usually stated if available.

guesthouses also could fit into this catergory as well.

Your wife has a very relevant concern, and you'll both fell much more comfortable with facilities in the room.

I've never stayed in a motel in Australia that doesn't have an ensuite bathroom, maybe its not mentioned as its just a given. And not many B&B's these days would expect you to share a bathroom. You probably would have to in a country pub though.

If you plan on taking the train Brisbane-Sydney, it departs Brisbane at 06:30 when NSW is on Daylight Savings Time, at 07:30 otherwise. And you need to be at the station at least 30 minutes before departure if you wish to check bags. So bear this in mind when deciding where and how far North of Brisbane you will stay. You may find it easier to spend your last night in Brisbane. The Holiday Inn is right at the Transit Centre from where the trains depart. The Ibis and the Sebel King George Square are both quite close.

As far as the train goes:
a) pay for First Class, more comfortable and less crowded.
b) book seats in the First Class Saloon car, not the Sleeping Car nor the Saloon/Buffet Car.
c) book one of these seat pairs: 9/10, 17/18, 25/26, 33/34, 41/42, 49/50 (or if none of those are available the pair two numbers higher eg. 11/12 on the opposite side of the train). This will give you a full window beside your seats for better viewing.
To do this you can't book online, must contact Countrylink by phone, 61-2-4907-7501 (06:30 to 22:00).