With regards to right click actions, use the Cashew (top right corner of the screen) to access the Desktop Settings. In there you should find a "Mouse Actions" tab. My guess is that you are somehow missing an action for "Right Click", which you can add here.

The version of KDE you are running can be found out from Help > About KDE, in any KDE application. For the minimize functions, are the windows still decorated? (ie. have a title which allows them to be moved around, etc).

Is the desktop otherwise normal? Have you installed anything to remove the cashew? It would help if you could post a screenshot.