opening pages gives 404 errors

My site, http://www.articlesandtexticles.co.uk has been working fine since April 2006. I always upgrade the same day as new versions are released.
Twelve days ago, I try to access my dashboard and I’m confronted with a page I have never seen before, that tells me that I must re-install WordPress.
I re-install WordPress 2.9.2 via FTP, and get the same error page, so I roll back to my latest backup, drop all the MySQL tables and rebuild the database. I flush the browser’s cache and history, etc.

I also find a big error_log (405kb)in the root of the site that shows multiple references like this:

[06-Jun-2010 07:22:11] WordPress database error MySQL server has gone away for query UPDATE wp_options SET option_value = ‘1275812531’ WHERE option_name = ‘_site_transient_timeout_theme_roots’ made by require, require_once, include, get_header, locate_template, load_template, require_once, wp_head, do_action, call_user_func_array, locale_stylesheet, get_locale_stylesheet_uri, get_stylesheet_directory_uri, get_theme_root_uri, get_theme_roots, get_themes, set_site_transient, update_site_option, update_option
[06-Jun-2010 07:22:11] WordPress database error MySQL server has gone away for query SELECT option_value FROM wp_options WHERE option_name = ‘1’ LIMIT 1 made by require, require_once, include, get_header, locate_template, load_template, require_once, wp_head, do_action, call_user_func_array, oneBitJsHead, get_settings, get_option
[06-Jun-2010 07:22:11] WordPress database error MySQL server has gone away for query SELECT * FROM wp_users WHERE ID = 1 LIMIT 1 made by require, require_once, include, get_header, locate_template, load_template, require_once, wp_head, do_action, call_user_func_array, All_in_One_SEO_Pack->wp_head, ob_end_flush, All_in_One_SEO_Pack->output_callback_for_title, All_in_One_SEO_Pack->rewrite_title, get_userdata

(URL for the error_log is available on request)

Everything seems to be as normal. I download the error_log and delete it from the ftp site so that any newly generated error_log will be apparent. None appeared.

The next thing that happened was that my stats collapsed from the normal (1000 – 2000 visits a day) down to 5 – 20 visitors.
Image <img src=”http://i292.photobucket.com/albums/mm19/satoriguru/a_t_stats.png&#8221; border=”0″ alt=”Articles&Texticles_stats_06Jun2010″>“>here.

Some visitors can see the site, but many cannot. When I try to open pages I get 404 errors:-

Not Found
The requested URL /series/ was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

My hosting company suggests the following:

As per error logs, Table ‘animatio_arttext.wp_commentmeta’ doesn’t exist in your database animatio_arttext, hence query “SELECT comment_id FROM wp_commentmeta WHERE meta_key = ‘_wp_trash_meta_time’ AND meta_value < ‘1260836178’ made by do_action_ref_array, call_user_func_array, wp_scheduled_delete” doesn’t execute complete.

You will have to create table animatio_arttext.wp_commentmeta in your database or either contact with WP’s support team.

Regards,
Eric
Support Tech.

As I have already re-installed WordPress and rebuilt the database, I can’t see what more I need to do to restore my site to full functionality.
Any thoughts or suggestions? Please?