Not very good with this but I will try to explain. (old fellow 69Yrs)
HP 554E PC Windows XP SP2 Set for auto updates & drivers.
Computer has shut down about 4 or 5 times by itself. Got an error message last time. ntfs.sys missing or corrupt error message.
I received the following when asking for help on it.
1 boot computer with the Windows XP CD-ROM in the CD-Rom drive. ETC. ETC.
Now that is the problem... It came installed and no CD-Rom.
I do have a Windows xp Home Edition Upgrade CD.

Welcome to the PCHF Bob! No such thing as old fellow, only 'used bones'

Can you please insert the Windows XP Home Upgrade CD and goto Start -> Run -> type in sfc /scannow

This will scan your computer for all system files that have been changed/corrupt/deleted.

Once you've finished this, can you please follow the link in my signiture to our 'Prework' page and post the resulting logs? One of the security team will have a look at it for you and make sure you haven't been infected by a virus or something similar.

Getting nowhere..
Put CD in and program opens up??

Yup, just exit that and continue on with the Start -> Run

Start is the bottom left corner of your screen.

Just want to thank you for all of the help. I posted results of scans. Everything seems to be working fine this morning. (Old Bones)

Excellent, marked as fixed.