Thanks to all...it's certainly a confusing problem.
After searching on all forums I could think of I found an old thread discussion the same problem...
http://www.retouchpro.com/forums/inp...ht=web+colours
On this thread Racc's solution was to work with Colour Management turned off when preparing any work for the web... I had stumbled across this possible approach too.
While MattMatic's eventual solution was to strip all the profiles from his Display Colour Management Settings...which sounds like doing the same thing and making your display non colour managed (like a web browser)...but not sure what it would do for one's printing.
So the question is are these really the best solutions...it sounds like it may be more of a problem with LCD screens, but any further suggestions would be very welcome.
Many thanks again for all help already offered,
Cheers,
Paul