Defragmentation & Desktop Cleanup

Defragmentation
Go to run and type defrag.exe this will run the defragmentation program, with the help of defragmentation you can rearrange your data in your hard disk.

Desktop Cleanup
You can change the desktop cleanup process through registry editor, (through display properties you can on or off desktop cleanup wizards)
Hkey_Current_User \ Software \ Microsoft \ Windows \ Currentversion \ Explorer \ Desktop \ Cleanupwiz (here you can change the interval of clean up process)