Hi
To help increase your chances of being invited to a recruitment day - go back over your application and see if there is anything you have forgotten - or anything that you could add.
Perhaps have a read thoroughly over the Virgin Blue website and look for key words that are used to decribe the people that they are looking for - then use them in your application.
As for the "kindergarten games' - in my interview for QF - we were required to build a plane with lego, make a tree from cardboard, look at a situation of some folks in a lifeboat and then vote one person out of the lifeboat.
As you can see, DJ are not the only ones to use this type of activity to see the real you - and weed out the folks that unfortuneatly do not have the qualities that particular carrier is looking for.
Good Luck!