* desktop.ini = They're required for folder customizations such as if you have a "My Download Files" folder and use your own user selected icon, therefore deleting the desktop.ini file would remove the customization. They're also used elsewhere by Windows by default so you could mess up something just blindly deleting them!
* folder.* = Not a good ideal since they have a legitimate use for folder.jpg, etc., for album covers/art and that would for sure upset allot of people.
* Icon Cache = Not a good ideal. Who would want the icon cache rebuilt everytime after running CCleaner, it's a once in a while thing to run at best if icons aren't showing correctly.
You can always use other tools where you can specify which files you yourself deem as "junk" to clean them out.