You have the 2 18 gigs as RAID 1 Mirror and the other two Raid 5 Right. You will have to install the 36 gig drives RAID 1 and then RAID 5 the new 146 gigs. you are starting from scratch. Windows XP does allow data swap under certian circumstances but I don't think you can get there with all new drives in 2000.
Noli Nothis Permittere Te Terere!!
EVGA 680i, Dual EVGA 8800GT'S (650/950), 4 gigs OCZ DDR2 1066, Intel Q9450 at 3.8 Ghz, Koolance Water Cooled, Dual Plextor16x DL DVD+/-RW. Dual WD 250gb 16mb Cache Sata 3.0. 3DMark06 score = 19,168.