Not a problem - we're here to help.
Since you're learning, I'm going to include a lot more detail in my posts so that you can understand why I make the suggestions that I do.
Putting an XP hard drive into a system that it wasn't installed on will usually result in a BSOD.
XP doesn't have the features to recognize and install any newly required drivers. Things get better with Vista and Windows 7 - but they're still not 100% perfect.
Did you install Windows 7 on the contractors hard drive while it was in the laptop? If not, would the contractor mind if you installed your copy of Windows 7 onto his hard drive in your laptop (it'll wipe out the XP installation)? FYI - you can also do a Repair Install of XP (if the contractor OK's it) using the instructions here: http://www.michaelstevenstech.com/XPrepairinstall.htm
If you are running Windows 7 on the contractor's hard drive:
- have you visited Windows Update and gotten all available updates (to include hardware drivers and other optional updates)?
- have you checked in Device Manager to ensure that there are no unknown/uninstalled devices?
What I'm trying to figure out here is if the system was setup/installed with enough updated drivers for us to figure out if it's hardware or software. A spare hard drive that you can install Windows on is a great tool to figure this out without having to wipe out your current installation (the one on the other hard drive).
Hardware black screens aren't as common as software black screens - so we'll have to be sure before suggesting replacing the laptop!
I've spent weeks at work troubleshooting black screen errors without success. We now just try System Restore - and if it doesn't work we call up the customer and tell them we've got to wipe the system and reinstall Windows.
If you can get back into Windows the first thing is to set a System Restore point (so you can get back in again). The Windows Installer doesn't work in Safe Mode, so you'll need to be in normal mode for the last 2 steps.
The next thing is to backup all your stuff - in case you can't get back into Windows again!
The next thing is to update all drivers with the most recent versions available from the device manufacturer (NOT the PC manufacturer)
The next thing is to get ALL available Windows Updates - to include the optional updates.
If you can't get into Windows, try System Restore (from Startup Repair) to see if you can find a way back into Windows. If you do, start with the stuff above.
If not, then the procedure is:
- make sure you have your recovery disks
- backup your stuff
- wipe the hard drive (I use KillDisk, but DBAN works just as well - both are free with a Google search).
- Clean install Windows in order to test it (instructions here: Canned Speeches
Post back with any questions that you may have.