Critical customer website about to go live when we just discover that it's not appearing correctly in IE 8 and 9. Screen shots of the Google Chrome display, where it looks perfect, compared to an IE8 instance are attached. It's mostly occurring with the top menu going vertical instead of horizontal, and the centering is off.
I'm told this is most likely a CSS issue, but with my limited knowledge of CSS, I'm not even sure where to begin to correct this or provide a workaround. Any help would be greatly appreciated!