Welcome to TSF.
You need to install at least Service Pack 1 - preferably SP 2.
Run TestDisk on /dev/sdb. (eject the XP disc - it's only confusing

)
testdiskselect2.jpg
A. At the first window, select
No Log and press the <
Enter> key.
B. Select which drive to analyse, choose
Proceed and <
Enter>.
C. Select partition type Intel if its a PC then <
Enter>.
D. Choose
Advanced > press <
Enter>.
E. Choose
Boot > press <
Enter>.
New screen - please post back with a screenshot.
How to post a screenshot.