Hi Alfredo
Well it would depend on your sense of adventure, ages of people involved and height of people.
Dreamworld, great family wise but if you have small kids not that good due to rides being adventous. Also the height requirements are 120cm to 140cm not sure but worth checking out before had. Check out
www.dreamworld.com.au
Seaworld more animal and family friendly, not as many big rides but heaps of animal shows to watch.
www.seaworld.com.au
Movie world something for everyone more kid friendly with characters like bugs bunny and marvin etc wandering around. Also rides for the big kids.
www.movieworld.com.au
Wet n wild. Great for the whole family heaps of water rides should be nice and warm around then. They have added new rides. If you wish to go here best day to go even if it might be crowded is Saturday as the park stays open late for the dive in movie. You can sit in banana chairs on the ground or on a tube in the wave pool. (Its not going during the movie.) A giant screen goes up for the movie.
www.wetnwild.com.au
If you are a member of NRMA or RACQ etc you may be able to get cheaper tickets before arriving or multi passes to a few different ones.
Best thing to do would be to look at the abovementioned websites all the places have there own pros and cons. When you decide which ones you wish to go to I might be able to tell you more about the places. As living in Brisbane it is only 45 minutes down the road LOL LOL.
There are extra things you can do at each if you wish to spend the money. Also take a few water bottles for yourself and save some money that way. All places have lockers that you can hire for the day for about $10. Some places you can take your own food as long as it isn't commerically prepared eg in a companies packaging.
I will send this to you in a pm as well just to make sure you get it.
Thanks AJ