fatal error when logining in or trying to view posts

This happened out of the blue, I get these errors when trying to login or view posts

standardbyke.com/blog

Fatal error: Call to undefined function: get_option() in /home/standard/public_html/blog/wp-admin/admin.php on line 21

this when logining in and this

Fatal error: Call to undefined function: wp() in /home/standard/public_html/blog/wp-blog-header.php on line 14

when going to the home page of the blog.

This site has run problem free for almost 3 years, we recently added a theme, but things were running fine. Nothing of significance was added or deleted from the site.

I am not the most savy when setting up these directories and all the config files, so I am flying pretty much blind. I have removed the plugins, reinstalled WP7 and the theme, plus removed the theme completely, all with no luck.

Please help.