I'd like top tips around the following problem:

An amount be the easiest method to edit a webpage which has 2x posts through the editor?

You can test it using the Custom Field Template. For that first column you should use the default editor of Wordpress but for the second you may create a custom area where the wordpress plugin shows a textarea with TinyMCE support.

Posible code for that "custom area template" to exhibit a textarea inside a custom area area:

type = textarea
rows = 4
cols = 40
tinyMCE = true
htmlEditor = true
mediaButton = true

(you need to enter that code in wordpress-admin panel from the wordpress plugin).

To obtain the data in the custom area inside your web site-file you should use the get_post_custom_values function:

//returns an array
$colum_2_content = get_post_custom_values("column_2", $post_id);
echo $colum_2_content [0];