hi flood4,
you have several options:
- "Ghost" or clone the old hard drive to the new drive.
- Borrow a windows xp installer cd, use it to install windows, but use the license key that you have
- Try to contact the brand and manufacturer of your laptop.desktop. Ask them if its possible to acquire the installer cd. They would probably charge you some $$ for this cd.
- Or simply purchase a new license for Windows 7 -- i think this would be the best option.
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Ghost/Cloning/disc-to-disc copy of old drive to the new one
This solution requires you to have cloning software like Norton Ghost or Acronis True Image. Of course acquiring this software would be an additional purchase on your part. The idea is to use hard drive cloning software to entirely copy your old hard drive and paste it to the new one. This isnt technically simple to do, it depends on the cloning software that you will use.
Norton Ghost (current version is Ghost 15) 
or Try Acronis True Image 
Norton Ghost and Acronis True Image are one of the popular and long time competing brands for disc cloning and hard drive backups.
An advantage of using hard drive cloning software is that you can use it for future backups of your entire hard drive.
2. Borrow a windows xp installer cd -- most likely you will need an OEM type windows xp installer cd. Unless your previous windows xp installation was made through a Corporate Volume License CD, then you will need to look for one as well. Try borrowing first from friends/family, purchasing used Windows XP cd and license key from eBay is not always effective. Besides, you will be using your own windows xp license key.
3. Contact the brand and manufacturer of your laptop. Ask for the Windows installer disc OR Recovery disc.
4. Purchase a new Windows 7 license! I think this would be the best option. Learn and get acquainted with Windows 7. This gets you updated on the latest Windows OS, and gives you better compatibility with programs, better online security, and easier plug-n-play with old and new hardware.
This page takes you to the purchase of Windows 7
Purchase Windows 7 Upgrades and Featured Accessories
This is a screenshot of the comparison between Windows 7 versions.
For purposes of being practical and budget friendly, i suggest Windows 7 Home Premium. This version will do for home, school, work and small business purposes.
The features that are NOT included in Windows 7 Home Premium, i will try to explain what i can below:
Connect to company networks easily and more securely with Domain Join.
This feature is required only if you will be using your computer on a corporate network environment. This featyre will only be needed if you will be using that computer to connect to a wireless or wired connection in an office that requires special login to a "domain". For free wifi hotspots, coffee shops, schools, and even small business wifi, this is rarely required. It is safe to skip on this feature.
In addition to full-system Backup and Restore found in all editions, you can back up to a home or business network
Well, every method of backup is nice. But there are already a lot of free and very cheap backup methods. Online backup methods like Dropbox and Mozy are cheap and give plenty of storage. Manual backup methods through external hard drives is one of the easiest and cheapest backup methods.
Work in the language of your choice and switch between any of 35 languages.
Unless you need to input in different languages other than the local language of the cd that you will buy, then you will need this feature and should consider purchasing Windows 7 Professional.
Help protect data on your PC and portable storage devices against loss or theft with BitLocker.
Bitlocker is basically builtin encryption that is available only on Windows 7 Professional and Ultimate editions. Bitlocker allows you to securely encrypt your files OR entire Windows system so that in case of theft, your data is safe and cannot be copied. While this is a great security feature, it requires you to save a copy of the decryption keys. In case of future computer problems, you will need the decryption key to copy the files from the encrypted hard drive to the backup. If you lose the decryption key, then you lose chance of recovering your own system. Bitlocker is a powerful security feature, and also requires your active responsibility for keeping the decryption keys stored in a safe place.
There are already lot of free encryption software that works the same as Bitlocker. If you want encryption but do not want to spend extra for Windows 7 Ultimate, check out "TrueCrypt"
TrueCrypt - Free Open-Source On-The-Fly Disk Encryption Software for Windows 7/Vista/XP, Mac OS X and Linux Run Windows XP productivity programs.
This is the "Windows XP Compatibility Mode" of Windows 7. You only need this if you cannot do away with programs that are compatible only with Windows XP. Unless you you legacy DOS and Windows XP specific software, you can skip this feature.
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Goodluck on whatever method you choose, see you again here in SysChat
