Plugin Manager Repository Update Fails

Version 6.9

Following error happens when I click "The repository is out of date. Update it by clicking here." in the Plugin Manager. I'm new to Drupal and it has been a slow start due to things like this already so any help to move on would be great. Thanks in advance.

I'm developing http://www.cutselect.co.uk and choose Drupal to build what will be a social network/trade directory. I look forward to finding out exactly what Drupal can do.

Ryan

Warning: MySQL client ran out of memory query: SELECT * FROM drupal_system WHERE type = 'theme' in /home/sites/cutselect.co.uk/public_html/includes/database.mysql.inc on line 128

Warning: Lost connection to MySQL server during query query: SELECT data, created, headers, expire, serialized FROM drupal_cache WHERE cid = 'theme_registry:' in /home/sites/cutselect.co.uk/public_html/includes/database.mysql.inc on line 128

Fatal error: Out of memory (allocated 11534336) (tried to allocate 4864 bytes) in /home/sites/cutselect.co.uk/public_html/modules/block/block.admin.inc on line 266

Warning: MySQL server has gone away query: UPDATE drupal_sessions SET uid = 1, cache = 0, hostname = '80.192.50.127', session = 'updates_remaining|a:0:{}messages|a:1:{s:5:\"error\";a:1:{i:0;s:273:\"warning: simplexml_load_string() [function.simplexml-load-string]: (null)Entity: line 86517: parser error : out of memory error in /home/sites/cutselect.co.uk/public_html/modules/plugin_manager/plugin_manager.module on line 277.\";}}', timestamp = 1244205427 WHERE sid = '1a153636c3cd050dffa46a3a815e4919' in /home/sites/cutselect.co.uk/public_html/includes/database.mysql.inc on line 128

Warning: MySQL server has gone away query: UPDATE drupal_users SET access = 1244205427 WHERE uid = 1 in /home/sites/cutselect.co.uk/public_html/includes/database.mysql.inc on line 128