If you use Windows 7 on a touchscreen device, there is a way to right-click documented here
"Press and hold does the same thing as right-clicking an item. To perform the action, touch the screen where you want to right-click, hold until a complete circle appears, and then lift your finger. The shortcut menu appears after you lift your finger."
This works on the Windows notification area and in apps such as Firefox, for example, but not in the classic start menu. If you hold down over a program item it just launches that prograam, instead of showing a context menu.