[Mark B]

Moving the operating system isnt a good idea.

Depending on how big your current drive is, you are probably better off doing this...

-Buy a larger internal drive. (Cheaper than an external)
-Install it, put a fresh copy of windows XP on the new drive
-Then move all of your personal files from the small, old drive to the new drive.
-If your existing drive is a decent size, you can keep it and use it for holding your music, movies, photos etc. That will keep the new drive clean to run your new operating system. If you decide to keep your old drive, make sure your format it after moving all of the files you want to keep onto your new drive. That will make sure you only have one operating system on your computer.