Newer browsers allow you to detect the user's screen resolution using the screen.width and screen.height properties. This can be a helpful way to send viewers to the right version of your page, depending on their computer's screen resolution. However, I am not sure if this is useful.

If I use any of my pcs that have screen resolution above 1440 width, I normally have many windows open. Very rarely do I want to open the whole screen. Unless I want to concentrate on a page with no clutter.
 

That is probably the behaviour that most people want. so if this was done automatically then I would not be happy since the window I like to use is normally set about 900px or there about in width

This is the script that people use in static pages. So to implement it in DNN, it needs to be injectected with a script injector module.

<SCRIPT language="JavaScript">

<!--
if ((screen.width>=1024) && (screen.height>=768))
{
 window.location="highres.html";
}
else
{
  window.location="lowres.html";
}
//-->
</SCRIPT>