In some versions of IE (mainly IE6 and IE7), the CSS needs to be updated to work correctly in some cases. This is a bug with those versions of IE, and all we can really do is use conditional statements to fix it.
As for the zooming issues, your point is taken. However, I am not sure zooming a pixel based layout is going to look perfect on a lot of sites out there. Using % or ems based units scale better than px based units. Those units are not a fixed size, thus they are designed to be more dynamic in their rendering.
Testing out the zoom level in a few browsers, it appears the entire page is zoomed and the overall page structure is kept intact for me. Is it possible that IE7 is zooming the text only? That could be why the containers are losing their structure and you are seeing issues.