When you install a operating system is it installed the hard disk? If so if I switch hard disks will it run the operating system on that hard disk? Thanks in advance
Yes it will, but you may need to install new drivers for the other computer. I used to do the same thing with hot swap drive trays, and also when I got my new laptop.
Install them like you would normally for a new OS installation. Plug your hard drive into your other computer, boot up, and look at your device manager. Correct any problem that you have either with your driver disk or manually finding hardware drivers on the internet. All you are doing is making sure windows and your new (different) hardware recognize each other.
Can you help me with this other problem? Well something is wrong with one of my computers operating system (it was running xp) and it says to put in the windows xp cd I forget the name but is it possible i can make a windows xp boot cd.
Is Windows working now on the computer? Why does it need the cd? The Windows disk itself will boot. I myself have never made an additional boot disk, but you can learn to make one here: http://www.windowsnetworking.com/articles_tutorials/Building-Using-Windows-XP-Boot-Disk.html