Your "template" is telling the browser it conforms to XHTML Transitional. When you use inline javascript you must add appropriate tags to tell the borwser (and validation engine) the content should be treated as character data (instead of parsed as structured data).
Code:
<script type="text/javascript">
//<![CDATA[
/* Add your javascript here inside the character data block */
//]]>
</script>
Some other things you "may" wish to consider:
- I see more than one "base" element in the "head". This should be corrected.
- Multiple elements with the same "id" attribute (some are also empty). This should be corrected.
- All elements need to be closed. This also applies to "br" elements. For XHTML they should be "<br />".
- Images should have "alt" tags specified.
- For jQuery plugins (like slimbox) why are you using inline javascript (increasing the page size / download time) instead of using an external file (which can leverage caching and reduce the overall amount of data required when viewing a second page or coming back to the site)?