Ok guys..... so you want to replace your hard drive?
first thing your going to HAVE to do is, BACK-UP i cant stress that enough. You never want to get stuck with a brand spankin new hard drive without the information from your old one.
Second thing you will want to do is make sure you have the OS instillation disk of your choice i.e...(2000,xp,vista)
Third thing is to unscrew side panel on your computers case and put off to the side. then remove the screws on the side of the drive bay to remove hard drive.

Fourth thing your going to want to do is remove your IDE cable and Power cable then leave hanging from motherboard for the new hard drive.
Fifth step is to take ahold of your NEW hard drive and put IDE cable back in and ensure tightness by wiggling it around if it doesn't move then your good. Now you can put the power cord back in

Step six your ready to go after you format and install the OS of your choice(refer to software)[code]