Nobody can tell you the correct keyword density %. The only way to achieve an appropriate density is to read your content and make sure it does not sounds like a spammer In the case of META description / keywords, follow the style of the current top ranking sites
Create your content for humans first of all. Then compare the keyword density of your site to the other sites on the first page for your keywords and tweak if needed.
I agree that your content should be created with your visitors first in mind. I typically shoot for a keyword density of 3% - 6%, which makes for a natural read and also easy targeting for the search engines. I'd also advise that you optimize each page for no more than three keywords (including your meta tags) - any more and you may dilute your results in the SERPs, and too many more may trigger a spam penalty. HTH, Sam
my content is for visitors - it is a fun site not a MFA or something like that. I have a section of games and the categories are action games, adventure games, fun games, etc. Should I remove "games" and have only adventure, action, etc ?
To be honest, I think you're better off with phrases, e.g. "adventure games", etc. Both strategies will work, and I've seen credible websites using both, as well - but by separating the phrases into separate words, e.g. "action", you're now targeting phrases that have nothing to do with your site's content, e.g. "action figures", "action films", etc. Just my opinion, for what it's worth... Sam