search engine & security

I know a little about search engine because it's important for a website. And I'm a little confused with things like "meaningful title" and "keyword". I know we should make a meaningful title and keywords about our website. It will be easy for the search engine to tell what's your website about and both for your clients. The problem is since it's a key for search engine, many website repeat their keywords - words often used to search for their businesses, then they are more possible to be found by clients. Then the title like "welcome to my ..." doesn't work well. Something like "Products, services, Products, services, Products, services, Products, services, Products, services, Products, services, ..." can be found here and there. It's annoying.
Anyway, I have to find a way out.
"Learn how looking at the ways people find and use your web site can give you valuable insight into your marketing campaigns, your page content and your products. Our Analytics articles cover topics like why you should be tracking your analytics, which analytics programs to use and what you should be doing with the data you gather." http://www.searchengineguide.com/marketing.html
"The Basic Task of a Search Engine

Our goal is to build a search engine that returns the most relevant results to searchers. To do this, we need to have a comprehensive index that is as spam-free as possible. We also need to create ranking algorithms which are able to determine the value to searchers of a given site in relation to their query.

We build our index through these 4 simple steps:

1. Crawl the entire Web
2. Analyze the content of every crawled page
3. Build a connectivity map for the entire Web
4. Process this data so that we can respond to arbitrary user queries with the best answers from the Web in less than 1 second."

http://searchenginewatch.com/showPage.html?page=3624905
I should go over it later, just save it here as a bookmark now.

Security is another important issue. But it's too much for me... The lucky thing is I know little about IT but my sister is an internet security engineer. So I can find some help if I have to do something with internet security later. Anyway, it's good to get a rough idea about what are involved in the whole process and some relevant knowledge, products, etc., like iphone.