Ill give you guys a tip.
Buy an additional laptop HD. and connect it via USB2 via a connector. Basically you slide the HD into a sleek aluminium case about a mm bigger than the HD on all sides. Then connect via USB2. You can just leave the aluminium case (housing your HD) in it's black leather pouch when you do this.http://www.coolerexpress.com/me930.htmlhttp://www.welland.com.tw/html/case/930.htmlhttp://pkab.com.pl/sklepik/images/ME930U2.jpg
Here comes the tip. If your smart, you'll take out your original laptop HD, then take the external one out of the housing and insert it into your laptop.
Now install XP, and get rid of the swapfile (just wastes space).
Now take out the external drive and reinsert your original.
Now you have a bootable external drive with a working copy of XP.
Just use it as an external storage drive via USB2.
But if you ever find your XP installation screwed so you can't boot, and you have crucial data on that thrashed disk. Just take the external out of the housing, insert it into your laptop, and boot. Take the thrashed HD, insert it into the housing, connect via USB2 and copy all crucial data.
Then put the original back into the laptop and format it.