A damaged or missing ntfs.sys file can cause the ntfs sys blue screen. You can replace the file with a new one by using the Recovery Console. To do so, you need your installation CD (some computers may have the Recovery Console function preinstalled). Firstly, you need to boot from the Disc and when you see the 'Welcome' screen you will need to select 'repair' by pressing 'R.'
For the Command Prompt, you need to select the installation you want to login to, then enter the administrator password (if you have one). Next, you want to rename the ntfs.sys file so that you can replace it with a new one. Enter the following commands (** being your CD ROM drive letter):
Then hit 'Enter'
ren ntfs.sys ntfs.old
Hit 'Enter' again. And then type:
copy **:\i386\ntfs.sys drive:\windows\system32\drivers
Once you've done that you can quit, remove the CD and reboot your computer. Alternatively, you can try a repair install which should replace the ntfs.sys file automatically. Unlike a full System reinstallation you will not lose any applications installed, and your settings and data should not be touched. It would be wise, however to make copies of all your data, in case something goes wrong. A repair install should replace all of Windows system files, but you will lose any Windows updates that were previously installed.
Possible hardware issues with video cards, RAM or hard drive can also cause the ntfs.sys blue screen. Test the memory and hard drive for any errors with a diagnostics application. You could also try swapping hardware to see if you can locate the source of problem. I wouldn't advise any manual changes done to your PC unless you know what you're doing. This goes for any system changes too, as you might cause damage to your computer.
If your computer has an AMD processor, then upgrading to a newer Windows Service Pack may trigger an endless loop of blue screens on startup. This is usually caused by a duplicate registry entry. If you experience blue screens after an update, you can install a patch to remove the problem. If BSODs still occur, you may want to first uninstall the update through the 'recovery console' and then installing the patch, before reinstalling the updated service pack.
To remove registry problems and other errors automatically download this registry cleaner.