The start
command can start windows maximized, but not scaled to a specific size. And browser security will prevent you from using JavaScript within the target web page's code to resize the client window.
Best bet is to use the InternetExplorer.Application
COM object to interact with an Internet Explorer window, rather than attempting to manipulate the user's unknown default browser.
Here's one possible solution. Save it with a .bat extension and run it to see what happens.
<!-- // batch / HTA hybrid script
@echo off
start calc.exe
rem // invoke HTA chimera for VBScript
mshta "%~f0"
rem // end main runtime
goto :EOF
// HTA chimera -->
<script language="VBscript">
Set IE = CreateObject("InternetExplorer.Application")
IE.navigate2 "http://stackoverflow.com/"
IE.width = 600
IE.height = 600
IE.visible = true
close()
</script>
You could also interact with the InternetExplorer.Application
COM object with a JScript hybrid or Powershell script if you prefer.