You can get great information at the oficial city of Seattle website: http://ci.seattle.wa.us . If you use Windows Explorer, you may find that Bing search is the easiest way to pull up the site.
For your information, you can use this url pattern to find the official site for any city in the United States: ci.cityname.stateabbreviation.us .
Also, on one of my web sites, karenmcknight.kwrealty.com , there is a link to good research on Seattle under the "Communities I Serve" title.
Good luck in your research. I think you will find properties in the Seattle area more expensive than in Danville.
Years ago we moved to W. Seattle from Bellevue. My wife was concerned with safety so we called a local police precinct there. As it turns out, compared to where we were living, it was safer. Anything can happen in any neighborhood, but some do have more issues than others. As Kary and Tonya have suggested, do your research and decide what your comfort level is.
I've attached a link from the Seattle Police as a place to get started.