wprock

Contact with your host. It is hosting problem. Some how your MySQL server is down now

copy the code from functions.php file and put in pastebin.com. After that share the pastebin link here.then we can fix the code

try this onclick="JavaScript: _gaq.push(['_trackEvent', 'Next Page']);"

Some JS is conflicting. You can manually upload the wp-admin and wp-includes folder of WP 3.5.1 via FTP and check once it.

You can use it List category posts

Try this one

<?php
function twentytwelvechild_custom_excerpt_length( $length ) {
  return 100;
}
add_filter( 'excerpt_length', 'twentytwelvechild_custom_excerpt_length');

function twentytwelvechild_new_excerpt_more($more) {
 global $post;
 return ' <a href="'. get_permalink($post->ID) . '">Read the rest...</a>';
}

add_filter('excerpt_more', 'twentytwelvechild_new_excerpt_more');
?>

Try this plugin WordPress Random Image