walkaflock on "Changing Width of text column, and deleting starter post?"

Hi All, my website is here : http://themasterplan.me/
I've been trying to accomplish a couple of things for the past few hours. The first is to change the color on the post background like so:
https://postimg.org/image/9nk1hf9vb/

I want all that white to be changed to a different color.

Alteatively I could also just stretch my text out to fill the whole white box, I can't figure either out.

The second thing is getting rid of the first post except, and having my first post directly on the home page.

https://postimg.org/image/g2j2e3gl3/

Hopefully my horrible paint pictures helped understand what I'm trying to accomplish.
Thanks!