Yes, I understand what you meant about spooling. I meant more in terms of in checking your local/client printers list to see if there is something installed on there that could override the PrtSct function - there are some third party software like PDF printers, Tiff/imagers that can bind themselves to the key.
Personally, I don't know why X print is on your PC as it seems could be more for development or client-server related purposes. The average user wouldn't have it installed.
Looks like Outlook users may also have it installed by default:
OL2000: General Information About the XPrint Control and Add-in