WP_Posts database crashed – HELP!

I need some help fixing my husbands blog – Guitar Licks. Today when he visited the site (while I was still sleeping) the blog had error messages stating that the WP_posts database had crashed.

When you visit his site it loads with the WP theme and sidebars, but there’s error messages at the top and a “post cannot be found” message where current posts should be listed on the index page.

Some of the errors state:

ALTER TABLE wp_posts ADD FULLTEXT `yarpp_title` ( `post_title`)

ALTER TABLE wp_posts ADD FULLTEXT `yarpp_content` ( `post_content`)

So I’m assuming this error has something to do with the Yet another related post plugin that I’m using on most of my blogs. This blog is using the plugin version 2.16 and is using WP 2.62.

In the Yet another related posts plugin admin area there was a message that said:

YARPP’s “consider titles” and “consider bodies” relatedness criteria require your wp_posts table to use the MyISAM storage engine, but the table seems to be using the engine. These two options have been disabled.
To restore these features, please update your wp_posts table by executing the following SQL directive: ALTER TABLE `wp_posts` ENGINE = MyISAM; . No data will be erased by altering the table’s engine, although there are performance implications.
If, despite this check, you are sure that wp_posts is using the MyISAM engine, press this magic button:

I clicked on the “magic button” as the plugin seems to be working just fine in all of my other blogs and I ended up with even more errors!

Help!

I’ve looked at the WP database for this blog and the WP_posts table says “in use” and I can’t browse it. I also can’t use the backup plugin in Guitar licks – it’s there and functioning but just hung when I tried to do a back up.

I’ve backed up the whole database using PHPmyAdmin so I have a copy in case something goes terribley wrong. Now I just need to know how to fix it.

Should I just place a check mark on WP_posts and then click the repair function at the bottom of the structure screen in PHPmyAdmin and see if that repairs the problem?

I’m nervous about attempting to fix this as I’ve never had to try to repair a database error before. Any help would be appreciated.