WordPress is not build for pages, its more for the posts. Page Management is not very smooth yet.
This can be critical if you try building a static Website with WordPress with lots of pages in it. Setting the page order and managing parent and sub pages can be very (very) (very) confusing.
Here is a plugin that makes life so much easier.
WordPress Page Management with pageMash
pageMash is a simple and cool WordPress plugin that makes managing pages very easy. Once installed, the plugin add a menu item pageMash under the Pages on the left sidebar of WordPress admin.
The interface looks like:
The pages are listed here according to their Page Order. so if you list pages somewhere on the blog using wp_list_pages the pages would appear in the exact same order.
To move a page up or down, just drag and drop it there. A parent page can be made a sub-page of any other page by dropping it over to the second page. Simple as that.
You will love this plugin, give it a good rating!