plugin error/wp-settings.php on line 113

*argh*
This is my first time using php and mysql [imagine my shock when i got this blog up relatively quickly] and i am having an error across the top of my page: “Warning: Invalid argument supplied for foreach() in /wp-settings.php on line 113”
This error seems to be emanating from the plugins [on the plugin page i get the errors “Warning: in_array(): Wrong datatype for second argument in /virtual/velvet/public_html/alexserpa/wordpress/wp-admin/plugins.php on line ” This error appears 3 times, along with the 3 default plugins [which are not activated and cannot be activated]
This was my first install of wordpress and no plugins are activated. I tried adding a post to see if the ‘no posts in blog’ problem that i’d read of here was the prob, but that didn’t work … any advice? Thank you for your time
-daniel