I'm sorry you are having an issue with your device. With the information you have provided, contacting Samsung Service (please visit Samsung's website in your region for support numbers and links) would be your best next course of action since this seems to be a service issue.
I have a Samsung model LN26A450 LCD that suddenly will not switch on either with the remote or the switch on the side of the TV. The outlet works for other items. Is there some kind of reset? What could have happened? It is only three years old and rarely used.