This area is a deep one so before I write "look at the event viewer" it would be nice to know how many years you have been working with curing Windows ills. For example the first reply should not be what is the event viewer? This is not unlike wanting to change a part in a car and you don't know what a wrench is. At least with the internet you can research what a wrench is to avoid questions about tools.
If such research is unacceptable and you find that helping yourself is too much to ask, the usual fix is to restore the machine from its factory CDs then watch out in the future for things such as malware or "what you think can break it."
Microsoft has tried to ease the troubleshooting but it's still an advanced skill. You may want to skip all this and try GRIF'S ADVICE at http://forums.cnet.com/5208-6121_102-0.html?threadID=378815&tag=forums06;forum-threads
Tell more,
Bob
I've got a Sony VAIO F-Series laptop with 64-bit Windows 7 and I'm having a problem with the OS completely freezing up for 3-5 minutes upon start-up or waking up from sleep/hibernate. How can I check to see what is causing the problem and how to fix it?

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