Nikki, your house is awesome, I love your house. Seriously, I wish we'd been able to get something like that here.

There are 3-4 playcentres in Werribee and Hoppers Crossing. The best ones I have found are called Kidz Digz and Wonderland. I like the stuff at Wonderlad better, but the seating for parents is a bit of a PITA, its not as well laid out. The entry price is less though.
Kids digz still has good stuff (not as good) but the seating arrangements for adults are significantly better.

Which skatepark are you going to? There is one next to a large playground in WyndhamVale and another in Hoppers Crossing.