To force quit a program:
option+command+esc force quit

To force eject a volume called VolumeName, type this in a Terminal:
hdiutil eject -force /Volumes/VolumeName
or, type the following command, and then drag to eject the troubled volume:
hdiutil eject -force

To remove an icon from the toolbar:

Software such as MobileMe insert an icon on the toolbar. To remove an icon, press down the control button, then use the move to drag it off the toolbar.

There are several ways to do screen capture in Mac OS X.

Follow the steps below and you will be able to do a screen capture in Mac OS X.

• Switch to the screen that you wan to to do screen capture
• Hold down Apple key + Shift + 3 and release all
• then use your mouse to click on the screen
• Done. You will see a picture file in at your desktop. That is the screen capture picture.

You can also do a screen capture for a portion of your screen.

• Switch to the screen that you wan to to do screen capture
• Hold down Apple key + Shift + 4 and release all key
• Now, You will see the mouse cursor will change to +
• You can start to drag your mouse to select the portion you wish to capture.
• Once finish, you will see a picture file in at your desktop. That is the screen capture picture.

If you want to do a screen capture for a particular application window, you can follow this:-

• Switch to the screen that you wan to to do screen capture
• Hold down Apple key + Shift + 4 and release all key
• Now, You will see the mouse cursor will change to +
• Press the space bar once
• You will see the mouse cursor change to a camera
• Now you can use the camera to select which application window to screen capture
• Once finish, you will see a picture file in at your desktop. That is the screen capture picture.

To zoom in:
Control+scrool up with the mouse
Here, Control can be changed to Option or Command via System Preferences; Mouse