Ok, after further testing, i am not so sure that it has solved the problem, when i first added the file, it shutdown perfectly for a good number of tries.
Since yesterday however i have been getting long shutdown times, I get passed the part where it says saving your settings, and it then goes onto windows is shutting down. I have a 5 minute wait from the time i see the windows is shutting down screen til it actually does shutdown, there is 0 disc activity.
At the moment i am not 100% certain its avast thats doing it, it was before but i havent dug any deeper since its the holiday season, but i will start work on it next week and see what it says, but i still think that the nforce4 chipset is playing a major part in our shutdown probs, its either that or ACPI failure somewhere
hope you all had a good xmas and i wish you all a happy new year.