I'm not sure this will cure your exact problem but it won't do any harm.
The computer hesitates while windows "refreshes" all of the Desktop Icons. This is because the ShellIconCache file has reached it's limit of 500 entries.
To stop this run Regedit and open the key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer and Edit, New, String Value. Name it MaxCachedIcons and then right-click, Modify the value to 2000.