I am new to Atahualpa. (using Atahualpa 3.6.4) setting up my first site but cant seem to find where I set the page or site width.

using "The Layout WIDTH and type (FLUID or FIXED) %:: (tried % or px) It just seems to push the site to the right, not reduce it.
Tried on opera & FF. - Consistent results on both.

By this response its seem that this is not even the correct setting, but i cannot find anything remotely relevant on the on theme or on the forum so so sorry for asking something which I would of expected is obvious.

What is the URL?
What values did you put in each of the options there?

If you look at that page in the theme options you will not it says...

This setting must contain either % (percent) or px after the number.

Do you have a number? There are even examples on that page.