From a design standpoint, you may often like to include the contents of a page within a single table. However, doing so can slow down the time it takes for your Web page to appear to your viewers. Surely you've noticed pages where nothing happens and then all of the sudden, the entire page appears. That's because the contents within the table won't be displayed until the entire table is downloaded.
To rectify the situation, try splitting the page into separate tables. That way, the top tables will appear for the viewer to browse while the other tables render.