It would be very usefull if it is possible to resize the length of articles mainbody and increase it to 730 in order to be able to insert google ads in the text area of the articles.
I guess that after that I would have to resize the sidebar as well and that would be also usefull in order to use ads size 366x250.

How can I do that change?

Actually the template best fits 300x250 banners which are more marketable as well.

You can incorporate both 728x90 and 366x250 banners by tweaking your custom.css a bit

I've tried it but something is going wrong.
It's like the sidebar doesn't fit and moves after the mainboy of the article.

I checked your site and I could not see the #page .wrap { width: 1120px } rule.

You are right! I didn't pasted the "#"from the code you gave me.
Now it as I want it to be.

But this change created new resizing issues with the module suffixes.
Like:
modSlidingMovies
opinionMod k2EqualHeights
listModule whiteBg k2EqualHeights
editorsPick blockmod

also:
The social menu block at the right top position
The category listings presentation
and the template is not rensposive anymore.

Actually the template was developed for specific measures and 300 x 250 banners.

Forcing new dimensions will lead to unexpected behaviour.

ok! I'll keep like it is.
Looks better anyway