I believe what you are referring to is the past notification icon collection that gets rather large after a while. The solution is not particularly easy but does work. This is one issue that needs to be addressed in future OS's. It requires the use of regedit but is safe if you follow these instructions exactly. go>start\run and type in regedit and click ok. Now follow this route by clicking the + HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\TrayNotify
Now right click on Iconstreams and delete it. Then close out of regedit. Now right click on your taskbar and then click task manager and click the processes tab and then highlight explorer.exe and click end process. Leave the task manager open and on the top left of task manager click file\new task and type in explorer and click ok. Now your desktop will be there and the past icons will be gone. If you close task manager by error simply press ctrl+alt+del at the same time and it will reappear. Good luck.
