Hi, Considering the number of times you are going to have to do a back-up, it could eventually cost quite a lot in CD or DVD discs unless, of course, you use re-writeables.
If things ever go belly up and you have to re-install everything then this can be a long, laborious task.
You might like to consider buying another hard drive and then cloning all the contents of your main drive to it as often as you feel a back-up is necessary.
The advantage of this method is that cloning covers the operating system, the registry, the programs and all data files, etc, and, when things do go belly up then it's a simple matter to clone the contents of the back-up drive back on to the main drive. Much quicker and easier than all those CD discs!!!
I have been using this method for the last four years now with no problems.
You can read about it and download a suitable cloning program here. click here
Hope this helps.