Reza,

The width of your site is controlled by the skin, so you would need to edit the skin or find another one if your current skin doesn't look how you want it to.

There is no automated way to publish content from a test site to a production site, however doing that process manually is definitely the suggest method of deploying changes.

Hope it helps,

Maybe there is some content in your site that causes her skin to stretch, where the default DNN skin would have overflowed in some way.  The skin and containers are the only things that should be affecting the layout of your content.

I suppose it depends on what type of changes you are trying to deploy to your site.  If you are just talking about changes to content, then there isn't an easy way to move content from one site to another.  It might be easier to invest in a module like our Engage: Publish that lets you moderate content before it is displayed publicly.

If you are talking about changes to modules themselves, we would suggest using the standard module upgrade process (using a module package).  If you are talking about changes to skins, again, using skin packages will help alleviate difficulties.

Let me know if that helps, and if it makes sense to you,