Is there a website that can generate cool blog post titles and/or a tool that can generate good tags for sites?
Depends on how you define 'cool' really. As Dave said, those articles will help from an SEO perspective, though personally I just use "google adwords research tool" and "google search insights" (google them) to find most popular keywords. Generally, using the most accurate titles and tags is the best idea. Never try to fool the search engine by using misleading titles or keywords, thats a surefire to get delisted.
On the otherhand, perhaps you mean 'cool' as in… most likely to be shared around on social networks - 'diggable', as it were? In that case, lists are a great way to go "top 5 tools… " , "6 reasons why …." etc