Each XP installation has a Product Identification Number that is by license supposed to be displayed on a Microsoft Holographic imprinted sticker on the outside of the Tower Case if it is a Desktop or on the bottom of the Case if it is a Laptop. The "PIN" must match with the XP Installation CD.
Microsoft uses this PIN protocol to assure that a purchaser receives a license to use the XP operating system only on the one original machine that it was purchased with. It is "theoretically" possible to use an XP installation CD on a second or more machines, but when the user goes to the MS Update site for Critical Updates and Patches, any machine without the correct licensed copy of XP installed will "fail to Validate" and the necessary updates will be blocked for that user.
Therefore it is absolutely necessary for you to verify that you are using the correct Installation CD that came with the original equipment.
Here's a well respected source for Step-By-Step instructions for a clean install of Windows XP.
http://www.theeldergeek.com/xp_pro_install_-_graphic.htm
You should read it in its entirety, maybe more than once. You're not likely to foul things up for your machine, but it can be "tedious" especially to someone new to the task. If you find yourself totally overwhelmed, you can always have a local repair shop do this procedure for you. I'm sure they will tell you that they do it all the time, and may even admit that doing reinstallations is a major part of their business traffic.
There are many other educational and resource sites on the internet where you can learn about reformatting and re-installing XP. Some will even tell you about how to avoid the "product activation" sequence. Read carefully.
Most folks feel a bit intimidated the first time they start a reformat/reinstallation, but by the time they are finished they may feel a great sense of accomplishment and have less reluctance to try it on a second machine, or if needed a second time in the future on the same machine.
If your XP CD does not contain the SP2 upgrade, you will have to download it and burn it to CD, or purchase it from Microsoft, for about $9.00, here:
http://www.microsoft.com/windowsxp/sp2/default.mspx
After you've installed the XP installation, and "BEFORE" installing the SP2 upgrade, install DirectX 9.0c and the machines ChipSet Drivers.
Then install SP2
Then follow the list I outlined above for other drivers, etc.
Partitioning uses the XP installation CD's ability to "divide up" your hard drive into sections called "partitions" that will "act like" they are separate Hard Drives and will be identified with letters like C:\. D:\. E:\ etc.
Remember to "Format" each of them. This will require that you repeat the formating procedure for each Partition you set up.
So if you have an 40gb, 80gb or 160gb or larger, you can make separate partitions for your Operating System, your Office Application programs, your Gamin Applications, your Music files, your Family Pictures, and your General Documents and files.
You certainly don't "have to" partition, but if you do, you will likely start realizing the benefit after you use your system for a while.
Windows XP can be installed into as little as 1.5GB - 2GB of Hard Disk space, but in actual operation, XP needs more "room to manuever". So make your C:\ Partition about 10GB - 12GB. That should be no problem on today's large Hard Drives.
It's an interesting learning experience, and I wish you well with it.
Best Regards
Here's another resource site:
http://www.windowsreinstall.com/winxphome/…dexfullpage.htm