Plugin messing things up!

I installed the intouch plugin, in order to incorporate html forms into my pages. Know I can’t access my site or admin…………..visit my site and see……….. http://www.chrisfarris.info
Can I simply delete the plugin from the plugin folder or do I have to delete and/or turn off the plugin in the code of the program somewhere?

I am confused and do not know a lot about WP!
Please Help.