hi and hello hope this helps
Many programs will ask, before they install, if you want the program to be available to all users on the system or just the user who is installing the program. Some programs don't ask and just install the program for all users. When this happens you get the result that you are seeing.
There are 2 locations for the desktop in windows 7
\Desktop is the location for All Users. Any shortcut icon in
this folder will appear on every users desktop.
\Desktop is the location for each individual user. Any
shortcut icon in this folder will only appear on that invidual users
To get the result you want, If a programs installation places an icon in the all users desktop folder, you can simply move that icon from that folder to your individual desktop folder.
Note: You may get an administrator prompt when you add or remove icons from
the all users location.