1. Configuration of KDE
It is possible to configure KDE by modifying the configuration files kept in your .kde directory. However, nobody in their right mind would bother with this as it is much simpler to use the Configuration GUIs provided.
At the bottom of a KDE managed session is a taskbar, and on the left side of this (yes, coincidentally just where the Start button is in Windows !) is either (older systems) a large K superimposed on a wheel, or on recent Fedora systems, an "f" superimposed on a blue shape like this: , or on SUSE systems, a chameleon: . Henceforth this will be known as "Start". If you click on Start a menu is displayed, and the configuration options can be reached from here.
Clicking on Control Center will bring up The KDE control center, within this select Appearance & Themes (or Look & Feel in some versions) and you will access further windows allowing you to change the background, colours, fonts etc. An interesting one is the Theme Manager. Themes are integrated sets of configuration options bundled up which can be installed as a whole, without the need to individually configure every little thing. There are several themes available and there are many thousands more available over the Internet. They are usually downloaded as .tar.gz files - put one in a sensible location and click on the Install New Theme (Add in some versions) button in the Theme Manager window - this will bring up a browser which will allow you to locate and add the theme.
You can also access most of the individual windows that make up the KDE control center directly, for example right-clicking in the background will bring up a menu which includes Configure Desktop....
Similarly, right-clicking in the taskbar at the bottom of the screen will take you to Configure Panel..., which allows modifications to taskbar attributes.
Clicking on Start then Help will bring up The KDE Help center, providing access to lots of documentation. More information is available at www.kde.org.