setting the menu depth and resizing the image box

Hello I have two questions: 1. How do I set the menu depth? I would like to have main menu and sub-menu shown on the top menu bar, but not the sub-sub-menu. For example, I have "About" menu on the top and have "Policies" page under it. I also have some linked pages in the "Policies" page. I want to have "About" and "Policies" on the menu bar, but do not want child pages displayed on the top header menu bar. 2. How do I resize the content image box on the front page? Originally, the box is sized width:height=210:210. I would like to make it smaller to width:height=160:160 so that I don't need to scroll down so much to get the bottom of the page. Thank you so much in advance.