Website down, line 12, completely lost, please help

I don’t know what I am doing at all. I have a personal website that I update infrequently. Recently I was adding a new post and it said I had a bunch of plugin updates, so I just accepted them all. That caused my website to crash and gave me the following error:

Parse error: syntax error, unexpected ‘[‘, expecting ‘)’ in /home/content/49/7274949/html/wp-content/plugins/wordpress-23-related-posts-plugin/config.php on line 130

My site is hosted by GoDaddy. I reached out to them for help, they directed me to WordPress. I reached out to WordPress, they referred me back to GoDaddy. I then came to the forums here and a Support Team Volunteer advised me to delete the wordpress-23-related-posts plugin altogether because it is no longer supported. I did that and it just created a new error which seems even worse:

Warning: require_once(__DIR__/scb/load.php) [function.require-once]: failed to open stream: No such file or directory in /home/content/49/7274949/html/wp-content/plugins/wp-pagenavi/wp-pagenavi.php on line 12

Fatal error: require_once() [function.require]: Failed opening required ‘__DIR__/scb/load.php’ (include_path=’.:/usr/local/php5/lib/php’) in /home/content/49/7274949/html/wp-content/plugins/wp-pagenavi/wp-pagenavi.php on line 12

The Support Team Volunteer suggested reinstalling the wp-pagenavi plugin, but I don’t know how to do that. I am a simpleton and need to be talked to like a child in order to understand. I just want to be able to access my website. Can anybody help me?

The page I need help with: [log in to see the link]