Tartan Giant,
You could use
Ghost or
Acronis True Image to clone your hard drive and place it in your new computer.
The problem will be WinXP. It does not like all the changes in resources. At the very least you will need to do a repair with the WinXP CD and you might end up needing a fresh install on top of itself, using the WinXP CD, in order to get the OS running again.
Personally, if you have WinXP Pro, I would install it on the new computer and just transfer your files over to the new computer. Then install all your old programs and load your data.
Take Care,
Richard