Dear PeteC - I apologise for the hijacking, didn't realise that was a 'no no'. And thanks very much for the welcome
Anyway - when I sat down at my computer today it is showing the right time for the first time in months!!
Another thing I did yesterday was download a little program called Dimension 4 from Thinking Man Software which runs in the system tray. When I installed it yesterday it would synchronise my system for a fraction of a second before Windows jumped again to the incorrect time (which was anywhere from 30mins to a couple of hours, but not exactly on the hour ... like it would be 42 minutes ahead for awhile, then a couple of days later it would be and hour and 20 minutes ahead).
I assume that my kids have restarted the computer today and I figure that doing that with Dimension 4 loading at Start-up has somehow fixed the issue.
Anyway - thanks for the speedy response guys - looks like my computer decided to behave itself now that I called the big guns in!!