removing all feature for users besides POST

Basically i would like to have other users be able to post messages on my blog. however, i want users of , lets say for this example, level 1 to go to a page where they can only POST or Edit a message of their own. So it eliminates all the confusion of dashboard and makes it very simply for a user.

The directing people after login is not my current problem. Right now, I tried taking the post.php file and commenting out the require_once (‘./admin-header.php’) in the default section of the switch. Then I added get_header() right after it. Now when I go to the page I have all of the a€?write a post pagea€? on my theme. The problem is the a€?write a posta€? stuff is slightly wider then the theme. I was reading posts here saying making a theme wider isna€?t easy. So is there a way to make the theme slightly wider or the write a post page slight smaller? If need be I can create a new page, lets say post2.php, and have that be the single page for posting and editing and not change any of the wp-admin stuff. Is there a specific css file that the a€?write a posta€? page follows?