That would be a real nice surprise for your parents
Australia is a great place, lots of places to visit and wicked scenery, just one problem with Australia, it's full of Aussies
jk
You can look into a trip here to New Zealand, it's also a great place to visit and at the moment with our dollar being pretty low against the green-back you can get quite alot of scenery for your dollar.
NZ pretty well much caters for the tourist and has townships set up specifically for them, Queenstown has everything from white water rafting, bungy jumping.......and lots more
Check out this site for more on our backyard
http://www.newzealand.com/travel/International/