Shoutbox

I've seen a bunch of threads here asking about the background image size and such, but this isn't one of those.  I was wondering if there are any scripts out there that would resize my chat window to the images size size when I apply it, or perhaps at least keep the window in proportion to the image.  Or another option could be, is there a way that I can set the default window size for all chat windows, and not allow them to be resized?  I'm just really tired or either choosing to have crappy looking backgrounds, or fighting to get the window to just the right size for the image to look good.

Thanks in advance to anyone who can help me on this one ^_^