Timeout Errors from Saving Posts and Pages

This is one for the WordPress braniacs as it’s way above my paygrade.
Recently, a site located at http://bellydancevillage.com has been throwing errors when I update an existing page/post. Strangely enough these errors aren’t occurring with all pre-exising pages/posts and don’t occur at all when I create a new page, or post. It’s not the same error all the time. They’re of the same class usually but not always. Here’s a few results from recent save attempts;
Page URL
http://bellydancevillage.com/blog/lets-talk-belly-dancing-tips/
Error: Fatal error: Maximum execution time of 30 seconds exceeded in /home/leyla/public_html/wp-includes/post.php on line 439
Page URL
Same as above, 2nd save attempt
Fatal error: Maximum execution time of 30 seconds exceeded in /home/leyla/public_html/wp-includes/cache.php on line 287
Page URL: Same as the first, 3rd attempt
Fatal error: Maximum execution time of 30 seconds exceeded in /home/leyla/public_html/wp-content/plugins/wishlist-member/core/Functions.php on line 0
Oddly even though it errors out, the changes are saved.
I did the usual plug in deactivation, reactivation and the error was being caused only when WishList member was activated.
I sent the error message but so far they’ve only suggested that I increase the execution time using one of the three methods below
1. By Wp-config.php Changes

set_time_limit(300);

Important – If you are making changes in wp-config.php, then add this line above
“/* That’s all, stop editing! Happy blogging. */” comment.

2. In htaccess

php_value max_execution_time 300

3. Addition in php.ini file

max_execution_time = 300 ;
I don’t have access to php.ini so that was out of the question and they’re response did not address the fact that some error out, some don’t and new pages/posts never do. I am continuing to push them to look a little deeper.
I am also in the process of submitting ticket to Host Gator to see if there’s anything on the server level that is out of whack.

My gut however is telling me that there’s something wacked out with the WordPress install/configuration but I don’t have any way to troubleshoot this, hence the my reason for this post.
1. Has anyone ever encountered a situation like this and if so what was the cause/fix.
2. Does anyone have any avenues of investigation that can be implemented and tested short of doing a fresh install.

Any guidance, or support is appreciated in advance.
Thanks,
Dan

PS: The odd thing on top of this is that I have three other environments that are identical where I haven’t any issue at all. And when I mean identical, I mean identical. Theme, framework, plugins etc. They are relatively fresh installs and this is what is leading me to suspect that my WP install has gone wacky.
Thanks again