I think he was talking of actually physically taking out the hardrive from his old computer and putting it in his new one.
This is actually not really recommended because when you installed windows it programmed all it's drivers, ect... for the old computer so just plugging it in will not really work since it won't really know what to do with your new hardware.
One idea could be get a new hardrive and do like TMacK
said or you could back up all your files, write down youre isp info and stuff onto a DVD or some cds (don't try floppies you will ned ALOT
) or an external hardrive if you have one and once you have everthing backed up, format the drive then install it into the new computer and reinstall windows and then transfer all your stuff back.