Reducing the amount of HTML code (for the same amount of content) on a page will probably make it easier for the bots to spider it. Just make sure that there are no typos in the HTML code - especially unclosed tags, and nesting errors.
<div>'s have a major advantage over tables from a SEO standpoint. Tables are read left-to-right, top-to-bottom, period. <div>'s, on the other hand, can be displayed in a different order than they appear in the code.