comp : is there a way to clear out such security settings? or reset to defaults?

i'm going to sell it most likely and it has office 2003 pro, and xp pro (legit copies) which i could format and just pull their cd keys before hand but... sounds like alot of trouble. i ebayed the computer (dell optiplex 620 2.8pentium d, 512ram, 160gb,DVDRW) for $200, it sells on dells outlet site for almost 500.