if(something)
echo "something";
else
{
echo "opening the browser";
echo "<script language=\"Javascript\">\n";
echo "var window_name=window.open('file.html','window_name','height=300,width=500,directories=no,location=no,menubar=no,resizable=no,scrollbars=no,status=no,titlebar=no,toolbar=no');\n";
echo "</script>\n";
}
For the window attributes, look at
http://html.tucows.austriaone.at/programmer/jstut/jsTabWindow.html.
Hope this helped...