Hi there,
To get the featured image at the top of your page, you need to enable the Showcase Page template. To use the template, create or edit a page, and assign it to the Showcase Page template from the Page Attributes module. To make the Showcase Page template your front page, go to Settings → Reading and set the Front page option to Static Page. Select the page you just assigned the Showcase Page template to as your front page. Then you need to set the post with your front page image to be 'sticky' and the image to be 'featured'. Instructions for setting those can be found at:
http://en.support.wordpress.com/posts/post-visibility/#sticky-posts
http://en.support.wordpress.com/featured-images/#setting-a-featured-image
The way this theme is designed, enabling the featured image will push your right-hand column down so you won't be able to put your text to the right of this image. You can either put your text in the left-hand column next to the image, or you can put it in the right-hand column where it will appear immediately below the feature image.
You can customize the order of your blog's menu from your dashboard's Appearance -> Menus option.
http://en.support.wordpress.com/menus/
Does that answer all your questions?