If you just want two columns (which is what that code would make) then you only really need one table. If you are wanting to style the big table, then use a div instead. Dont add extra 'junk' tags where they arent needed. Strictly speaking, you shouldnt need to use tables at all to do a layout, you can use <div> 's to define the sections, then use CSS to place those wherever you like.
That makes it a lot easier to update too, since your HTML will only have content in, and the design will all be in the CSS. So yuo can change one, without having to ever see the other.
EDIT to add: here is how you could do the columns thing:
then either link in some CSS, or put it in the head...
<p>Left column content here</p>
<p>Right column content here</p>
//sets all padding and margins to 0 to help you position your elements
//style everything in your content - this would be the equivalent of your 'bigtable'
//position so the divs are next to each other
//add styling for yout left column
//then add styling for the right column