Pop up window (resized)

I have quite a few variations of the code, but which code do you recommend for resizing pop ups? (ex: you click on a link and a new screen at a set width and height pops up).

Thanks

 

http://www.codeave.com/javascript/code.asp?u_log=7065

 

That works but some browsers prevent resizing of the window.
I would use:

window.open('http://example.com', '', 'width=600, height=300');

Code (markup):

But then again, window.open is not very elegant either... what is it for? A "div" layer "on top" of the page might be a better option.