Backing up with Ghost 15

I just purchased Ghost 15 to back up my computer the other day.  I chose to make a full back-up of my C drive and also back-up my documents folder.  It only took a few minutes to back-up my C drive and documents folder and my C drive has 76.9 GB used.  I checked my external hard drive to see if and how big the back-up was and it is pretty small.  I have an image file that is only 512kb of my C drive, recovery environment file of computer name that is 5kb and a file backup data folder that is 1.38 GB.  Did it make a back-up of my computer so that if it fails I can restore it as is without intstalling the OS...etc. or just back-up my doc folder?  I have a second hard drive in my system that I put a lot of my programs on and was gonna back up as well so I would not have to reinstall and just restore both drives.  I just wanted to check to see if I was doing this right or if I messed something up.  I am running Windows XP SP3, and my external hard drive is 300 GB so it has more than enough room to back up my C drive that is 150GB.  Thanks for any and all help.