To further improve the "description" field quality, there are two additional techniques you can use.
First, you can define this value if you know it, by setting a description meta tag in the head section.
Second, mnogosearch has an <index></noindex> tag pair that appears to make the enclosed content completely invisible to the search engine. I've used this on the sites I maintain to 'vanish' the navigational elements, field names, and other non-content type HTML and page window dressing so that only the important content is indexed and reported on.
This last technique as an added (and more important benefit) of helping to eliminate a lot of false matches in searches.