How to take OS files from 1 harddrive, and put on another 1 without an OS disc?

I want to take the WinXP OS files from 1 harddrive and put them on another 1 to setup WinXP on it. I don't have an OS disc. Where can I find the files on my drive? Can I even do this? Is is illegal to do so?

You use a disk imaging program such as Norton's Ghost. Legal yes if you do not sell or transfer the OS to another system or person.

Check to see if you have a folder called "I386" on your hard drive. If you do, burn this to a cd and you'll have a Windows cd. It may be hidden in a recovery partition. You won't be able to boot from this disk so in order to install, you'll have to get a boot cd and burn it, boot from it and install that way. You can google a bootcd or use the ultimate bootcd at www.ultimatebootcd.com . It will take some trial and error and some time to figure out how to get windows installed, but generally, you can copy the i386 folder to the new hard drive, boot to it and run setup from there. To keep it legal, just be sure to wipe the original drive to remove windows after getting it setup on the new drive, just in case there's the urge to put it in a new machine or sell it. An easier solution which is borderline is to just find the exact version you have (XP home, pro, M, OEM, etc) on a torrent site and install it with your valid key. You'll be kinda questionable on downloading it, but it makes no sense that vendors won't just give you an OS cd. You should be able to download and install your licensed copy and then remove the old copy. The problem is, that if you use the wrong torrent site (say a popular one like thepiratebay), then when someone is monitoring torrents they may notice your download, contact your isp to warn you or worse, disconnect you or take you to court.