Hi Sophie
Just a quick word from an 'oldie' who emigrated in 1983 and has lived north of Brisbane ever since. There is lots of good advice on these pages. The North or South debate is a permanent issue around here. I prefer the north (find it less industrial and easier to negotiate) but I worked down south for many years - colleagues there couldn't conceive of living on the northside!
I agree with others that it may take a little while to find the perfect place for you - so you may have to move schools for the children. However, you are arriving at the start of the last term, which finishes in Dec -- followed by the summer holidays. By the time school goes back at the very end of January you may have had enough time for a good look around.
PLEASE don't worry about the wildlife - the spiders are generally harmless - even the enormous huntsman spiders which, I believe, are useful for catching other smaller insects. We have had more of a problem with ants, which descend in hordes on anything remotely edible - so we all keep our pest control up-to-date.
In 36 years I have seen only one snake in the wild around here - and that was only a carpet python. However, the advice to avoid long grass and make a lot of noise is good advice. I understand, as others have said, that some more rural places + the western suburbs are likely to have more snakes.
That's all for now - will add more later if I think of anything