Try to use text instead of images to display important names, content, or links. The Google crawler doesn't recognize text contained in images.
Make sure that your TITLE and ALT tags are descriptive and accurate.
Check for broken links and correct HTML.
If you decide to use dynamic pages (i.e., the URL contains a '?' character), be aware that not every search engine spider crawls dynamic pages as well as static pages. It helps to keep the parameters short and the number of them small.