It looks like the Featured Image panel has no effect on pages. Is that right? My option is to add media to the top of the page in the text editing window? In that case, can you tell me the ideal width to make the images? And is it at all possible for the image to go full width above the sidebar before the widgets start?
In pages the featured image works with the image format. When you’re editing a page, look in the right hand column for a box labeled formats. Choose image there to have the featured image displayed at the top of the page. That will cause the image to appear just above the page title. You could always place an image inside the content area of the page. To have an image there be full width, 700px should be fine for a page that has a sidebar. If there is no sidebar, then 960px will do the trick.