Good neighborhoods near Sacramento?

I need to know about Davis, CA and surrounding areas, such as Dixon, Woodland, Vacaville, etc. Can someone let me know what areas are good to live and what areas should be avoided (if any)? Specifics would be great, such as what neighborhoods are quiet and not-so-quiet; what streets (or specific areas) should be avoided and what are better areas, etc. Any info you have would be great.