Ahh good point felgall. Thanks. So I should go with "minimum width" like sunfighter mentioned.
Thanks sunfighter, I'll use that example you posted. Wondering, I'm using a popup that doesn't open a new window. Are you using some advanced popup blocking plugin? Because I have 'block popups' turned on in all of my browsers on my mac and pc's and it does not block these. It's the typical ones you see like a lightbox with an x in a circle on the top, right.