The ID would need to be changed in several related tables to avoid problems. If you need page order I would suggest the my-page-order plugin. It lets you organize your page order with an ajax interface.
If extra plugins aren't desirable you should be able to set page order in the edit page part of the admin. you would need to scroll down below the edit box a bit.
If changing the ID is for aesthetic reasons and you have mod-rewrite capability you might look into changing your permalink structure...if your blog is newer and you have no worries about confusing users and search engines.