It is important to realize that the 3rd layer of a WordPress website is the ‘Theme’. The 3 layers consist of (1) Database (MySQL), (2) WordPress itself (development environment, dashboard etc.) and (3) the Theme which sits on top and provides the interface that is seen by visitors to the site itself.
There are literally thousands of free themes out there and many people choose a theme that looks nice but fail to realize that a theme has to provide access to all of the features WordPress offers. Many of the free themes fall behind the updates provided by WordPress and by default, tie the user to an older technology. In my view, it is vital to get your choice of theme right. We use (almost exclusively) the StudioPress Genesis Framework Premium Themes.
There is a cost involved but as your website is a vital part of your online presence, a few dollars spent on the theme will reward you hugely in the long term. The premium themes keep up to date with WordPress technology and utilize the newer features such as Custom Menus, Dynamic Sidebars and Dynamic Home Pages, as well as providing massively superior Widget and Plugin support.
The moral of the story is that a Theme should be much more than just a pretty face over WordPress; it should enhance both the developer’s and the user’s experience.