'Okay, Houston, we've had a problem here.'
Well, XP is gone.
There was possibly erased (only) the partition table on the first hard disk, but XP is still there.
There is a tool called
http://www.cgsecurity.org/wiki/TestDisk_Step_By_StepTestDisk to recover partitions that can be missing, missing data etc if you have NOT formatted ...
It is very powerful but you should have some knowledge of computers, however, management is easy once you read the documentation. Windows is very "fussy" and once recovered the partition table you may have to recover the system from the Windows Recovery Console. (Another Houston problem...)
Pardus have the TestDisk package, so you can install with Pisi.
It is a very powerful tool that you must handle with care. Must run as root, so either read the wiki TestDisk...
If you can seethe partition table with TestDisk on Hard Disk at least you can recover and backup the data and almost certain that the entire system with a little patience.
Another problem is that you installed grub on the first disk and not can boot Pardus after the recovery, but it can also be fixed...
Welcome to the (home) world of forensic analysis!