removed sidebar but then changed width of contentcontainer.Homepage looks screwe

Hi guys,
i have a problem.
I want to remove the sidebar from my posts but when i do this i have a big gap of empty space on the right. So what i did was change the width of the contentcontainer from 532 to 900px. All is fine in posts but the homepage pictures looks screwed up.
What can i do to resolve this?

Here is the site i am talking about:

Tatoo
Ideas Corner

Something else:
I have the logo on the left side and on the right side i want to have an adsense banner.How can i add that next to it?I tried many things but it doesnt work.