My mother-in-law has a P4 desktop with two U160 drives, but she wants to go with one huge 400GB IDE drive. The SCSI's are hooked up obviously with a PCI controller card, can I just put the IDE drive in and plug it into the motherboard and copy everything right from the SCSI's to the new IDE drive?
Yes, if you download the proper software for the new drive, and it supports the scsi interface you can do it. Otherwise get ghost and make a boot floppy with the proper scsi driver and go that route. Or install a fresh copy of windows on the ide drive, then just dump your data.