It sounds like you have a lot of experience, and can certainly use that to demonstrate CV fillers such as excellent communication skills, adaptability to new tasks, customer service. Don't worry too much about the time out of the workforce as that is often the case with mature women, and there are still ways to make your application stand out (especially if you are willing to start lower down the ladder and work your way up).

Although you are computer literate already, would you consider doing an IT course at TAFE or through distance education? That would demonstrate that you are up to date with computing as well as demonstrate recent education and would open the doors to doing something that would push you intellectually a bit more, and you wouldn't necessarily have to start with the basics but could jump into something a bit more exciting.

Other options are volunteering in a field that interests you, to demonstrate people skills as much as anything. Helping at the school your older children attend can also be used to fill your CV and show that you have been busy in your time out of paid employment. Good luck