How Can I Repair My Installation Of Windows Xp Without Losing Data

Is there any other application that will repair corrupted files in Windows?

I tried repairing it using original Windows XP CD with repair option and tried in Safe Mode also,but still the problem is not solved.

Please tell me about third party tool that will start without entering into Windows because the OS is corrupted.

Can I use any tool that will boot from CD and repairs Windows without losing data. Thank you!