Hi Roger,
Try giving Optus another call. AFAIK they should give you that DNS server info (I'm with iPrimus & I don't even have to speak to anyone to get it...it's within an option in the phone menu). Maybe if you speak to a different person this time, you might have more joy

Also found this, see if it helps at all.
Optus DNS Server.... - Cable - OptusNet

Can't help you with the Norton Ghost question though....someone else will have to answer that one