Problems After updating to wordpress 3.5.1

After upgrading wordpress I've just noticed 2 issues:

firstly I get next message error:
"Notice: image_resize está obsoleto desde la versión 3.5. Utiliza wp_get_image_editor() en su lugar. in /home/u443582533/public_html/wp-includes/functions.php on line 2839"
how I can solve this issue?
you can check this error at:
www.geekland.hol.es

Second error is in the comments of the post. In each comment I have next error:
"Notice: Undefined offset: 0 in /home/u443582533/public_html/wp-includes/capabilities.php on line 1067"
You can check this error at:
http://geekland.hol.es/integrar-maqu...una-red-local/

thanks in advance