I have recently been asked and debated about whether a user should do a full system back up (which includes the operating system, settings, etc. ) or a partial back up (which includes my documents, my music, my pictures, desktop , favorites and if you still use outlook, the .pst file). I can tell you my choice with no quiver of a doubt, do only a partial back up. Why? Keep reading to find out.
Why Should You Do A Back Up?
Most reasons to do a back up is in case something happens to your hard drive. It could be because of software issues or hardware defects. Did you know that I rarely replace hard drives because of hardware defects? What I mean is, about 75% of the time when your system crashes, starts slowing down, you get the blue screen of death, windows will no longer boot, etc. is because of a software issue. It could be caused by the wonderful product called Windows or your system has been infected with yet another dreaded piece of spyware or a virus.
Where Do Virus/ Spyware Lurk?
So, the question is, what do viruses effect the most and where do they hide out? I can narrow this down pretty easily for you and tell you where it is not (usually). This is in a spot called My Documents. This is too easy for you to find so why would the virus hide itself there? A virus and spyware is usually hidden in the program folder, windows operating system folders or in hidden folders that normal users don’t even see. These are all folders that are being backed up in a full system back up.
Full System Back Up VS Partial Back Up
If you are doing a full system back up and you have a hard drive failure AND you have no virus/ spyware on your machine, you are okay and life will be good again shortly. Usually, though, you have to install the operating system anyway, then install your back up. This usually takes several hours to complete. Sometimes up to 3-4 hours to complete
If you have a slowing computer, system crashes/ freezes or you know your infected, do a full system recovery, add your additional software and then copy your basic files directly to your documents and you are done. You have just saved yourself 1/2 of the time, cleaned up your computer from the old software that you never use anymore, and are less frustrated.
Here is the break down of Full Back Up vs Partial Back Up

Here is the break down of Full Back Up vs Partial Back Up
Here are some vital tools that you can use with an external hard drive.
Partial Back up software
Allway Sync Free Sync Software
Sysnc Back Free - Sync Software
Full Back up software
Cobian Full System Back UpRebit - Easiest to use full system back upFree full system back up software solution