Screen Resolution

I know how to detect a visitor's screen resolution using JS but I want just more than that. How do you do so, after which,........ communicating the Width and Height values to the width and height size of a table so that the table fills up the entire screen for different screen resolutions?

I want the values to be inserted into the variables in the table properties, instead of the more usual, easy method of calling a whole different set of file with the right table size.