@dganntech: I’m from Australia, so I can probably help here 🙂
I’ve travelled lots of times from here to the States, and I won’t like – the flight is brutal unless you’re flying first class.
To keep busy, I watch as many in-flight movies as I can. They are 1.5-2 hours each, so watching two or three movies meant I got through around 6 hours of the flight.
Make sure you set your watch forward to correspond with Australian time so that you sleep when it’s night time in Australia to avoid jet lag. Sleep as much as you can at the appropriate time.
You will get two or three meals during the flight, so they will occupy you for around 1.5 hours in total.
With all that taken into account, you will probably have a good 5-6 hours of twiddling your thumbs and dying to get off the plane. Bring a book, magazines, crosswords and anything else to occupy yourself. Buy a Lonely Planet guide and make notes on the plane of places you want to visit.
And yes, I may be biased, but our beaches are pristine! If you’re most interested in beaches, I hope you’re coming at an appropriate time of the year (i.e. November – March?).
Aside from beaches though, there are so many other things to do. Melbourne has a very European city feel (really arty, tons of amazing laneways, cafes and restaurants), Sydney is a shopping mecca and of course there’s the Harbour Bridge and Opera House and Bondi Beach. You can go to Queensland and check out the Gold Coast, Surfer’s Paradise, The Great Barrier Reef, Brisbane (or “Brisvegas”, as it’s affectionately known). Then there’s central Australia (the outback) where you can see Ayers Rock (otherwise known as Uluru) and Western Australia, where you can visit wine region in Margaret River and also go surfing there or go to Broome, which is famous for the beaches.