what is a small note that display to provide about a button or describe the screen element
The page that displays the icons when you turn your computer on is called your home screen. Some people do call it the main screen as well.
the desktop
The Toolbar.
Your question is not very clear. If you are referring to the screen (monitor) of the system, it displays the graphics and the interface. If you are referring to the actual computer (most often called the tower) it holds the hard drive, video & sound cards, all of the wires, processors, and is where the power button is located.
bitmap fonts
Its Called The Computer, The Top Part Is Called The Screen The Metal Box Is Also Called The Hard-drive
The portion of the screen that displays when windows XP is loaded is called the Desktop. It features icons for different programs, the Taskbar and the Start Button.
log off or shut off computer
I think you are referring to the 'Task Bar'.
When you say button, the start button is called the power button and it turns power on/off. There is no start icon as you see on a windows computer. On Mac the equivalent is the Finder icon.
A computer screen can be called a few things. Most commonly, they are referred to as "Computer Monitors". They are also called "Computer Displays". Sometimes, they are referred to by the technology they employ to display an image, or by other physical characteristics of the device. For example, sometimes the abbreviation CRT is referring to a computer monitor. CRT stands for Cathode Ray Tube. CRT monitors are very similar to older televisions. Sometimes, monitors are called Flat Panel Displays. This usually means that it is an LCD monitor.
The left mouse button is the one which is mostly used by the computer user. It is used for clicking and double clicking objects. Clicking is used to select objects, whereas double clicking is used for opening objects on the computer. Another important thing that the left mouse button can be used for is dragging things on the computer. On the other hand, the right mouse button allows the computer user to select from a list of commands that can be used to instruct the computer to perform a certain action. It can be used to change the background of the computer, create folders, rename files and folders.