After logging in to your Google Webmaster account, you will see the list of sites that you have submitted to the webmaster account. Clicking on the site that you wish to study, will take you to the current status page for that website as displayed below:
The crawl errors provide details regarding the URLs Googlebot tried to crawl but could not. It is important that your go over these URLs in order to fix any issues. It could so happen that when Google bot visited, your page was not accessible. If those URLs exist, and if Googlebot cannot crawl the URLs, it means those URLs won’t show up on searching, and you will lose out on potential visitors.
Googlebot and most search engine bots find it difficult to index rich media formats. Googlebot will not be able to read texts that are embedded in images or in any other rich media files. If your site uses Java or other rich media files, you might want to ensure that Googlebot can access those without difficulty.
Search queries are very useful because this will provide you a list of keywords/key phrases for which your site showed up on the SERPs. The report will provide you the queries, impressions, click through rate, and the position of your site. If you find a lot of impressions and no clicks, it means no one is clicking on your site. You might want to work on the content and Meta tags to make it more attractive and relevant.
This page will provide you a report on any HTML related errors, improvements that you might consider making in order to make the most of your title and description tags. There is plenty of advice on Google Webmaster regarding optimizing your images so that it is in tune with the best practices.
The information, that you get at the Google Webmaster reports, is updated regularly, so you get to know and view the exact status of your website, what is going right, and what is not. Armed with this information, you can certainly take your web site to a better place than it is now.