Right click on the task bar. Click on unlock task bar. You will see a vertical double dotted line to the right of your icons. Drag this to the right until all are visible, then re-lock the task bar by right clicking a blank bit and clicking on Lock the Taskbar.
If your display is large enough that you can afford the screen real estate, you can have the task bar on two lines (I prefer it that way). While it is unlocked hover your mouse pointer on the top edge until a double headed arrow appears. click, hold and drag the edge upwards.
VoG is referring to the System notification area at the far right, where active prog items are displayed alongside the clock. I thought you were referring to the start program icons by the start button. Which of the above you use depends on which one you were talking about.