Branching scenario

I am somewhat new to version control systems and I need to solve a
problem. I have searched the srchives and I still believe that my
answer is in there but I have been unable to find it.

I have a sandbox/build machine set up. Edits are made on various
developer machines and checked in. All are tested on the sandbox and
some pre-release components are checked in. All of this code is for an
always evolving website. I need a flag of some sort that all developers
can set on the sandbox version that upgrades that code to production.
This way pre-release code can sit side by side with the current
production code. Again this is only for new directories on the website
that are under development.

example directory tree

---root
 |---index.jsp
 |---customer1 (release)
 | |---index.jsp
 | |---other.jsp
 |---customer2 (pre-release)
 | |---index.jsp
 | |---other.jsp

First, I thought I could use a release property but I cannot figure out
how to checkout based on a property and I cannot figure out how to move
the property on a single version(i.e version 123) to the same file
later(i.e. version 567). So I don't think this is going to work.

Second, I thought of using a production branch but merging files from
HEAD to the production branch seems too compilicated and I cannot figure
out how to test the code that is upgraded to production.

Third I think that I can provide access to the sandbox for loading test
directories that are not in source control. This does not make me very
happy in that I will lose the version while in development.

I believe that I am just not thinking about this correctly...

All help would be great!

-- 
Adam T. Gautier
adam_gautier@yahoo.com
(617) 557-9699