OOh I forgot to mention... visit Sydney Aquarium and Wildlife at Darling harbour also. These both are in Melbourne as well. You will be surprised to see Australi's wild life... I have also forgot to mention Sovereign Hills (old Gold Field), there is live museum or it is called theme park. They have setup the a city of 1850s and all people are working there in old costume, it is fantastic place I hav ever seen....

and yes make your mission that u have to see Kangroos and Koalas live on roads and trees. In case of Koalas, I touched it and spend some time with Koalas in Sydney Wild life but I had decided that I will see Kangroos live on roads or in jungles... and atlast I have seen them in Gipsland... OMG they were huge......

If someone ask from me which one was the best place, I will say, "I am in love with Great Ocean Road"......