Click on the "Start" button to open the Menu.
If there are any program icons that you do not want, right click on that icon and from the drop down menu that opens, click on "remove from list"
Do that on all unwanted icons until you have left only the three that you wish.
Then rght click on the "Start" button, and from the drop down menu that opens go properties>customize start menu>general and in there adjust the field "number of programs on start menu".............if you enter 0 ( zero) in there, it should prevent any further entries being added to the main Menu.