First of all, you'll need the WinXP floppy set (because your CD does not boot). The download links for these floppies are on
this page.
After you boot to these, access the Recovery Console. From here, you can perform the steps on the following page:
How to Repair the Boot Sector. (You will have to scroll down or click the link to the section about repairing the boot sector)
Essentially, you will copy the files "NTLDR" and "NTDETECT.COM" to your hard drive. If you have another computer, a copy of those files can also be found in the root of the hard drive (C:\)
- rp
edit: whoops.. forgot to add the first link