I think I'd leave the HDD in your PC and install XP on the drive. Uninstall as many drivers and things as you can and get it as bare bones as possible (ie, set your video resolution to 640x480, 16 color) and then move the drive back to your laptop and cross your fingers you don't BSOD before you're able to boot it all the way up and get on the network or USB device.
Trying to boot into safe mode may help that first time.
Copy over any critical (video, network, usb) drivers to the drive as possible before putting it back in the laptop, so you'll have them handy when XP asks for them.