I have a little more time now, so I'll "splain" some things...
It sounds like you have an old house. In an old house there is no telling what wiring you may find.
There may be old wiring, which when it was installed, was installed properly to code at that time. This stuff is pretty safe so far as it is not going to burn down your house*, but not as safe as modern electrical wiring which also has a great amount of protection from
electrocution built in.
*The insulation on old wiring can crumble, especially around light fixtures, then it is quite dangerous.
Then you can have "homeowner" work which was not done properly and could have a fire and/or
electrocution risk. The circuit breakers may be too large for the wiring used. The wire size used at the breaker panel may switch to a smaller size downstream and therefore the breaker is too large for the wiring. Junction boxes may not have been used. Outlets might have been added without installing an electrical box in the wall and lamp cord used in the wall to wire the outlet. No telling what my have been done!
So the thing is to learn how wiring *should* be done, then you can recognize dangerous wiring.
Then these days GFCI's protect people from
electrocution in wet areas like a bathroom, kitchen, garage, and outside.
AFCI circuits protect from arcing in all other rooms of the house where a GFCI is not required. (Depending on your local code.)
Tamper resistant outlets keep that kid from sticking a metal object into an outlet.
Whole house surge protectors protect your electronic gizmos from voltage surges.
The thing to do is learn all about this stuff. Find out which of these gizmos are required by your local electrical inspector's office.
Then before doing any re-wiring, I would suggest getting a couple of books on home electrical wiring and reading them cover to cover.
You should then know how things should be safely wired. And then be able to tell when looking at your old wiring if it is safe or not. Learn if you can leave it or if it needs replacement.
Here is a manufacturer's guide on some of the latest code changes for home electrical wiring...
http://www.homedepot.com/hdus/en_US/...n_codebook.pdf
Here they have a ton of books on electrical wiring...
http://www.buildersbook.com/Merchant...tegory_Code=40