What operating system??
Previous post have identified good options for XP and for Versions of Vista below the Business version Have used aconis to clone some OLD SCSI HDDs (W/ Windows 3.11) using win XP.
For win 7 and vista bus (or higher) a good backup utility is included. Under control panel select system, backup. select image your "C" drive and save image to DVDs or a usb HDD. When done it will prompt you to create a bootable restor disk. Worked great, screwed up my win 64 "C" drive and did a restore from image file - Only lost a few emails received after doing the image file.
I used the Acronis True Image WD Edition and worked real good. As I bought a 500GB WD HD to clone my 160GB fujitsi HD.
Was going to use the Paragon as I got that free on a giveaway but saw that there was a lot of recommendation of the Acronis so I used that one.