Flash menus on your website are not "spiderable" by search engines. Links inside them cannot be deciphered by search engines, so the pages they reference are invisible to search engines.

Basic HTML links from one page to another are best for search engines. Alternatively, use small images with links from them to the page of choice, making sure you include an Alt text with each image so the search engines know what the image is about and what the page being linked to is probably about.

Use Flash and Flash menus only on pages you do not care to be examined by search engines.