HD - he has a WD 250 GB SATA, Ive got Seagate 250 GB SATA
Gfx - he has ATi FrieGL 3100, Ive got ATi Radeon 9250
Mobo - yeah different - i built mine, he bought from dell - mine is a Soltek, hes got whatever is in a Dell precision workstation.
Disk defrag - i actually just helped him install xp pro again..so neither of us have defragged.
window settings - ive got A FEW diabled in xp, but am using a bunch in ATi hydravision, hes obv. ot them all on, he just installed xp.
os - we both have xp pro sp2...