I'm flying out to Sydney on Austrian later this month too as it was easily the cheapest option I could find. I have never flown outside Europe so thanks for the tips given in the thread.
I do have one question though. With getting the flight from Heathrow to Vienna and changing planes there, how easy is it to get a window seat on the flight from Vienna to Sydney? Will I be able to request it at Heathrow? Does anybody have any helpful advice for this at all?
Thanks!