META tags are now old-hat. AFAIK, no major search engine uses keyword meta anymore. However, Google and some others use the meta description for the display in the SERPS but this data isn't indexed with any positive value.
With regard to getting top keywords, you could try this SEO tools keyword density util here:
http://www.seochat.com/seo-tools/keyword-density/
The most useful thing to do is to write the description yourself and concentrate on getting text content in your pages. As they always say "content is king".