Go into Start / Run type "msconfig" and to startup and close all non-essential programs on the startup (just temporarily you can always put them back) and restart your computer, if it still gives the error it has got to be a system file, and you can email Mr. Bill Gates(Microsoft Tech Support,
www.microsoft.com) / Self-Imposed God and ask them.
I wouldnt recommend doing this though if you do not know what you are doing or what the essential startups are and what the non-essentials are.
By the way, yes, this does belong in the Help Forum.
Let me know how it turns out mate.