Keyword density quickie...

Hi, I keep seeing that 3-6% keyword density.

1) I presume that includes mention of the word in navigation and title (the whole html page).

2) I presume also that I can pick different keywords to target on each page of my site or will my site as a whole be better rated if I choose a set of word for the whole site?

These sound like simple questions, but I'm new to this lark...

Density will include titles, links etc. Don't forget to add 'alt' tags to images, 'title' attributes to links etc.

You should optimize each page as a seperate animal and target the keywords relevant to that page.

Normally the index would be a general, site wide keyworded page and others more specific for the information those pages contain.