Boot up into Windows, and once on the desktop, right click 'My Computer', and select' Properties'. In the new window that comes up, click the 'Advanced' tab. In the Advanced window, click on the 'Settings' button under 'Startup and Recovering'.
Now, you'll see a line of text saying:
'To edit the startup options file manually, click Edit.'
Do so, and click the 'Edit' button next to it.
Notepad should pop up with lines of boot code. Just remove the line of code that refers to Windows XP Professional Setup.
Hope you get things sorted.