WordPress themes are the starting place for the design and functionality of your website.
These are a few of my favorite themes (and plugins)
Twenty-twelve is the current basic theme for WordPress 3.5. It is a free, simple, responsive theme that is great for basic blogging. As a foundation for a great looking, more complex site, it needs additional coding.
With Weaver it is possible to create a beautiful site with very little coding expertise. There a lots of back-end feautures that are easy to explore. Weaver comes in free and Pro versions.
Headway is a drag and drop theme that enables user to place various blocks (header, content, menu, etc) anywhere on a page fairly easily to build unique templates.