There are several parts to this. One involves defining what the page served by the Arduino should look like. The example web server code shows all the analog pin's values. Changing that to show one digital pin's value is child's play.
I should also send an email to a predefined address when another input is active to signalize a failure condition of the circuit breaker.
Depending on the e-mail address that may be easy (SurferTim posted some code on the Playground) or impossible (the Arduino can not do SSL required by most e-mail service providers, for anti-spamming reasons).
After receiving the email the owner should be able to connect to the board and using a button be able to command one of the relay board to control the external circuit breaker.
Whether the user has or has not received the email is really irrelevant. All that the email does is alert the user to the need to do something by accessing the Arduino-as-server.
What the Arduino-as-server serves up should be a web page with a form with a submit button and action that directs back to the same server (the Arduino) and script (typically /).
When the Arduino receives the original GET request from the browser, it will look like GET /. When the submit button is pressed, the GET request might look like GET /?resetPin=7.
The Arduino needs to actually parse the request to determine what to do. Obviously, the / should return the page, while the /?resetPin=7 should tell the Arduino to serve the page (/) again, AND do something with the rest of the data.
I am not very familiar with programming
Then this is not the project for you.
the only examples I have found covers only portions of my project.
Of course. But, if you understand what they actually do, you can put the portions together with only a little glue to do what you want.
If any of you could send me some appropiate code for this project I would be very thankful to him.
How thankful ( $ )?