|14" laptops do not typically have the room for a second hard drive, it usually takes a 17" laptop in order to get a second drive bay, though many are not set up for them anyway.|
You could in theory clone the hard drive you have to a partition on a new larger hard drive and create a second larger partition for your personal files. This has some distinct advantages if you keep your OS and programs on the first partition and move all of your files to the second partition. This make back up, restore and recovery, and disk imaging much easier and still only requires the one drive bay and just about everything since XP supports 1TB drives without problems.
You have to be a little bit crazy to keep you from going insane.