Atahualpa looks terrible in Internet Explorer

Hello.

I have a problem I can not fix, my site does not look good in IE, specifically the area of the posts will not be shown where it should be, ¿does anyone have any idea how to fix it?

as additional data I included the following code on HTML inserts header:

<!--[if lt IE 7]>
<script src="http://ie7-js.googlecode.com/svn/version/xx.x/IE7.js" type="text/javascript"></script>
<![endif]-->

<!--[if lt IE 8]>
<script src="http://ie7-js.googlecode.com/svn/version/xx.x/IE8.js" type="text/javascript"></script>
<![endif]-->


the direction of my site:
http://impresosymaquiladosmonterrey.com/

thanks