How do i re install windows without data loss?

I recently had to change my motherboard due to a resistor setting alight and permanently ruining the functionality of my system. The only part replaced was the motherboard, however as windows saw this as a substantial change It will now not allow me to log onto my computer (I choose my account and it says I must activate) However I cant activate my account... So what I need to do is re install my windows without loosing my data. It is very important my hard disk does not get formatted because my data is vital

Previously someone wrote me a guide... this is the part that doesnt work for me...

4.

In the Windows XP Licensing Agreement, press F8 to agree to the license agreement.

5.

Make sure that your current installation of Windows XP is selected in the box, and then press R to repair Windows XP.

After i agree to license I am shown the partitions and it does NOT allow me to press r to repair. All help appreciated thx x

How do i re install windows without data loss?pc security

Install on a new hard drive, then transfer your data across (put the old drive in after you've installed XP on the new one).

When you re-install, make sure you make separate partitions for the system (C:\ - where Windows is installed) and your data (say, D:\). That way you can reinstall without fear of losing data.

How do i re install windows without data loss?symantic