What your father probably did is delete all the icons unaware that they were placed in the "All Users" folder which effects all users.
What you need to do is right click on the START button and select "Open All users" and then click on "Open" to understand what I mean...
When you right click on the START button and select "Open", you are opening the programs that are accessible to the current user. To customize icons available for specific users, go to:
C:\Documents and Settings\User name\Start Menu and then add selected icons in the Programs folder..