richnyc30
I assume that you use layout with content on the left and sidebar on the right. You can edit the grid layout in this file:
/templates/ja_argo/tpls/blocks/mainbody-content-left.php
(if you show layout with content on the right, edit another file: mainbody-content-right.php)
To enlarge the right column, you can change the span in the div tag of 't3-sidebar' to a bigger value like: span4, span6... but make sure that the total span is equal to 12
For example, the total grid is 12 (12 span), the inset is span3, when you change the right sidebar to span4, the main content section's width will be decreased.
Regards