There are several elements that can be optimized:
Search engines only show the first 70 characters of your titles. Keep them short, appealing and include carefully chosen keywords.
Usually search engines will show the first 160 characters of your Meta Description. They might also use information from DMOZ. You can prevent this byadding a Meta tag.
If your website has user reviews or user ratings (example: e-commerce, product ratings, opinions about restaurants), take advantage ofMicroformats (or RDF markup) to improve the appearance of your search results with rich snippets.