If you can't get to startup options by pressing F8 you will need to boot from XP cd and go to Recovery Console.
Steps
Remove the non-system disk from your boot device.
For example, remove the non-system disk from the floppy drive or the CD-ROM drive.
Change your computer’s boot sequence.
Make sure that your computer’s first boot sequence is the CD-ROM Drive.
Insert the Windows XP or Windows 2000 CD-ROM into the CD-ROM drive, and then restart the computer.
Click to select any options that are required to start the computer from the CD-ROM drive if you are prompted
When the “Welcome to Setup” screen appears, press R to start the Recovery Console.
If you have a dual-boot or multiple-boot computer, select the installation that you must access from the Recovery Console.
When you are prompted, type the Administrator password.
If the administrator password is blank, just press ENTER.
Enter in the following commands:
COPY X:i386NTLDR C: COPY X:i386NTDETECT.COM C: [where X=CD ROM Drive].
Enter also the following to check also the boot.ini:
type c:Boot.iniIf the following message appear “The system cannot find the file or directory specified” your Boot.ini file maybe missing or damaged. You can replace Boot.ini by creating another and save to a disk and copy it just like the instruction in number 8 by doing:COPY X:Boot.ini c:For creating a Boot.ini refer to http://support.microsoft.com/kb/318728.