Creating a CD copy of the entire system is definitely a good idea.
In our experience, CD-Rs are more reliable than CD-RWs. At around 50 cents a CD it is well worth making a copy of your entire system at least every term, dating the disc and never using it again (unless you have to rescue your system of course!). Yes, I know you are not going to do that so maybe once a year would be good?
There are lots of programs out there ("there" being an arbitrary description of all places and time including where and now you sit) that can be used to burn CD-Rs, even Windows can burn CDs now... please do it from time to time, if you ever need it... you'll be VERY pleased you did it!
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