SEO Pages for Codeigniter

[eluser]bennyhill[/eluser]
I want my user's profile pages indexed by search engines for SEO. The current URL i have is http://baseurl/controller/method/id
where id is a user's id (number). Is this Search Engine friendly? Or do I have to rewrite it like:

http://baseurl/controller/method/firstname-lastname

or

http://baseurl/controller/method/firstna...tname.html

??

Do I use htaccess, routes, or both?
Do I need to dynamically generate meta tags as well?
Also when a new user create an account, do I need to manually submit this new URL to google?