Ive just bought a differnt Dell D600 which I had

If both of the computers are Dell D600, chances are that you can just swap the internal disks. You'll then find all of your programs, data, emails, as if you never got a surge at all. Only thing, you'll need to swap the Windows adhesive with the product key too, or keep both. Also, this will likely void your Dell warranty unless done by a Dell approved technician.

Another thing that can be done and won't void anything (except the Windows license, for which you'll need the sticker swapping trick) is to fit the dead computer's disk into an external USB case, then use a tool such as Linux Forensics or UBCD to dump the external disk onto the internal D600 disk. This has better be done by a data recovery expert: you run no risk of losing the old data, but you do run the risk of erasing the new D600 without being able to get it to boot again (until reformatted).

Also possible (but even more complicated), voiding neither Dell nor Windows licenses, is to dock the old disk in an USB case and "bring it alive" with VMware P2V. You'll get a old-PC-within-the-new-PC which will probably run slow as molasses, BUT will support virtual-USBing and the "Files and Setting Data Transfer Wizard" which is supplied on both XP and Vista. It will take some time but you can get most programs transferred. Many others will be transferrable with utilities such as Move Me:

http://www.tweakxp.com/article37624.aspx