Well, it turned out to be remarkably simple to switch my not very technically adept parents from Windows XP to Ubuntu (Breezy Badger). We did this on the basis that it was getting increasingly difficult to manage their computer difficulties from Melbourne, and their Windows XP installation was incredibly spamware and adware ridden.

So at the moment I have put Ubuntu on as a second boot option, just in case they ABSOLUTELY NEED TO use windows. But they tell me that they are only using Ubuntu.  In Linux, I have given their user accounts the standard (low) level of access, and I have made sure that I can get ssh access externally. Now I just need to set up VNC and dynamic domain registration so that I don't have to keep getting dad to lookup his modems external IP address.

Mark that one up as another successful switch to Linux. It was a lot easier than I thought. Their main applications that they used are Firefox, Outlook and some Microsoft Word.