Repeat after me Billy is your Friend... Trust Microsoft. Unless you fdisked the drive and removed the old partition and reformatted you have old windows settings lurking around on the disk that Mr Gates knows you really wanted to keep. You will never see these hidden files using a windows operating system. I ran a straight upgrade for about a month and the install started getting hinky so I fdisked, reinstalled and had no problems. Your main problem is you are seriously out of space. I've got XP on 1.9 gig and office directory takes up 290mb but I remember it claimed to need 450mb for complete install. I'm running a 20GB but have another 40 I keep data files on. The price of drives is a parabola that shifts as the next latest/greatest version comes out. I can't find A 20GB drive, 40s are $39.99 after rebates at compusa. What's you motherboard bus speed? I'd buy the biggest drive your board supports.