Windows XP uses the NTFS file formatting system.
Is the 300GB hard drive formatted on NTFS? If so, then I don't think you'll need to format at all. It should work fine.
If it is not on NTFS, then I can't help you there. I'm on Windows 98 and the only way to format a hard drive on my computer is to boot it using a boot disk and reformat it manually with MS-DOS.
I'm sure other people here would know the proper method since most people here use Windows XP.
Sometimes, it feels as though my life is just a never-ending circle of pain and misery. Not to mention sadness, worthlessness, and humiliation. But I can only cry inside. Deep behind my happy smile and bright personality is a sad and lonely person, a mere figment of my former self. Someday, all this pain will be over. I will drop down and die. At other times I ask myself, \"If only this would happen right now\".