If it was part of a Domain it is very likely that there are a lot of security built in preventing the end user from installing any Software or making changes to Windows. As such this Load is trashed and you'll need to install it again and ideally wipe the HDD to delete anything on it.
You can use something like Boot & Nuke to write zero's to every sector of the HDD and this will destroy any references to the Domain Controls that where previously installed. You can download Boot & Nuke from here
http://www.dban.org/download
If you don't have a floppy drive in this computer get the CD ISO and after you have downloaded it make a CD from it and boot off that CD and type in [b]autonuke[/b] this should run straight away and destroy all the data on the drive.
Then insert the Windows XP Install Disc and run the setup procedure. When it is finished you'll need to install the various drivers if it is a M$ Branded Install Disc or if it is a System Makers Recovery Disc it will install everything that came loaded on this system when it was new.
The only possible problem here is if you are using a M$ Branded Install Disc and this system has a SATA HDD you may be required to make s Slipstreamed install Disc to include the SATA Driver if it is required you can do that by reading the article here
http://tinyurl.com/6pfqo8
Download the same article from here and use those directions
http://tinyurl.com/5q2jsw
While these are written to include SP2 for XP the addition of a SATA Driver is exactly the same and is covered here
Or use a product like nLite to do the same thing
http://www.nliteos.com/download.html
If you chose to use nLite make sure that you read the directions for use located here
http://www.nliteos.com/guides.html
So in answer to your questions
[i]Is there any way to install one HD windows onto the other?[/i]
Answer Only if they are Identical Hardware if they are not the system [b]Will Not[/b] Boot when you move the HDD to the second computer.
[i]Such as a master and slave drives.[/i]
No
[i]If so which would be first?[/i]
Doesn't apply
[i]Or is there some software that will either fix the problem or let me in to formatt it?
Maybe some DOS command with a switch I haven't try.[/i]
Boot & Nuke as listed above.
I'm still not sure what it is you have downloaded to the HDD though but no matter it's not able to be used as the computer has either AD or GP settings on it which prevent this.
Col