Most people would use a CMS (content management system) which is designed so that people with no coding experience can update isolated sections of a web page.
See http://www.snippetedit.com/ for simple edits of text or images where you set out the tags which someone can access with a username and password or use a better one:-
http://www.joomla.org/
Code downloaded to my PC will be deleted in due course.
WIN7; IE9, Firefox, Opera, Chrome and Safari for Windows; screen resolution usually 1366*768.
Also IE6 on W98 with 800*600 and IE8 on Vista 1440*900.