Edit your boot.ini file on your XP Hard drive.
Insert the line below the similar looking line for XP:
multi(0)disk(0)rdisk(1)partition(1)\WINNT="Microsoft Windows 2000 Professional" /fastdetect
Edit the ARC path if necessary, you should only have to modify the rdisk(x) #:
ARC Path Defined=
multi(x) - Specifies SCSI controller iwth the bios, or non-SCSI controller. x=ordinal number of controller
scsi(x) - Defines SCSI controller with the bios disabled. x = ordinal number of controller
disk(x) - Defines SCSI disk which the OS resides on. When multi is used, x=0. When scsi is used, x = the SCSI ID Number of the disk with the OS.
rdisk(x) - Defines disk which the OS resides on. Used when OS does not reside on a SCSI disk. x=0-1 if on primary controller. x=2-3 if on a multi-channel EIDE controller.
partiotion(x) - Specifies partition number which the OS resides on. x = cardinal number of partition, and the lowest possible value is 1.