I haven't used the personal edition of ghost (which is most commonly found in stores) for a little while but I know you can save the hard drive to an image file. I'm not sure if it will let you do that over the network though to a remote location. At worse if you had an extra hard drive to put in there you can save the image to that (and that would be the image file so it wouldn't overwrite any other data on there). I'd probably be best just to clone the old drive to the new drive in the new computer.
Word of warning though Windows is going to be upset if you clone it onto a computer with different hardware than the old one. Small changes like video card, sound, etc. aren't that bad but I'm not sure if they removed the security feature from XP that will cause it not to boot if you change the hard drive controller on it.