Thank you FreewareFan for your comments, I will keep your experience in mind.
I too had a number of system crashes, not caused by a hibernation though.
It is very disturbing when fatal system crashes occur. You need then to reinstall your operating system which is very inconvenient because you need to setup your settings, modifications and programs back the way you like them and with which your computer works best. If you want to try to avoid re-installation of OS, there are a number of things that can be done in case of a fatal (unrecoverable) system crash instead of ultimate solution (clean install) :(((
Considering Windows XP, you can try the following procedure in case you cannot boot your Windows installation:
1. Insert your Windows XP CD
2. Make your system boot from CD
3. After the loading completes, press "R" to enter Recovery Console.
4. Login to your Windows installation (typically press "1" and type Admin password)
5. After you login, you can type (without quotes) the following commands:
- "fixboot" (will write new standard bootblock to boot area of HDD)
- "fixmbr" (will fix the Master Boot Record. Not that dangerous as one might think.)
- "chkdsk /p" (will repair your HD from filesystem errors, this version on CD is a little different.)
- "exit" (will reset your computer, before that remember to remove CD and set/allow computer to boot from Hard drive...if you are lucky Windows will happily boot again, no need for OS re-installation this time)
Also, there are several other things Recovery Console can do, such as instantly fix that "NTLDR is missing" problem etc.
Also, as a preventive measure to any system crashes and/or system instability, it is recommended to use a good Registry & Disk Cleaner tool, disk Defragmenter utility (but not that included with Windows) and do the "chkdsk" (directly from Windows session, no need for CD) once in a while.
CHKDSK is like a Disk Doctor, it will check for and fix any "hidden" filesystem errors that might evolve into system crash(es) one day.
You can use both graphical and Command-line way.
I recommend command-line so that you can see what exactly is wrong with your Hard disk filesystem.
It is very simple:
1. Click Start, then click "Run..."
2. Type "cmd" (all without quotes)
3. Command line will open, type in "chkdsk" and press enter.
4. After scan completes, see in report whether any errors are found.
5. If no errors are found, just type "exit" and press enter. That's it, lucky you.
6. If it says that errors are found, type "chkdsk" again and press enter. This is because of possible false alarm which occur sometimes.
7. If after second scanning, this time no error is found, type "exit" and press enter. That's it.
8. But if error is found then type "chkdsk /f"
9. Confirm with "Y" and type "exit" or click "X" on window, Command line window will close.
10. Next time before you boot Windows, chkdsk will automatically repair your system Hard disk.
You can also use other parameters and scan other drives for filesystem errors.
If you are interested, type "chkdsk /?" for complete list of parameters.
Please note: chkdsk is a very powerful tool, use it only to do checking not-so-often or if needed!
Hope this was valuable information. I see a lot of people around various forums asking about the same issues, but often you can luckily avoid the re-installation or, even better, prevent need for it entirely.
Still, doing backups of your most valuable files is invaluable practice.
Sorry for such a long post that might not be of entertaining nature to some of the readers.