What are the things that owner should watch out for before optimizing his website in the search engines?
According to my opinion, before to optimize site for search engines, you need to first analyze the market and its current treads. You need to know that who are your customers and what they want. Your website should be fulfilled your visitors needs as well as your business requirements. Your website design should be seo-friendly and user-friendly. You need to do competitor analysis also. After this your have search the best keywords to optimize site for search engines.
I agreed with Alan Smith he has given us valid points about website. Avoid making flash sites, normally Search Engine could find difficult to crawl your site.