If you had a Microsoft (retail) version of XP you could move it to a new computer.

Microsoft would remove the key association from your old motherboard and transfer it to the new one.

The basic principle is one key = one computer. The key is tied to the motherboard.

As to your question: can you move a Compaq XP: probably not.

If it were possible you'd have to run the reinstall CD's from Compaq and if they were to work you would then have to call Microsoft and see if they will transfer the key.

I doubt it will work but you can always try. The Compaq XP is OEM or proprietary to Compaq. Depending on how they set up their Recovery CD it may not even load on a non Compaq system.

You can use a free Linux OS on your new computer such as Ubuntu:

http://www.ubuntu.com/