To speed up your computer, and to keep your desktop clutter-free, how about consolidating all those files onto a single folder on your desktop? Better yet, keep the folder tucked-away in your Documents folder and make a copy of it by dragging it to the Dock for quick and easy access.
Believe it or not, each file and folder on the desktop has to be redrawn by the graphics processor; the more the clutter, the slower the computer. The human eye and brain cannot sense nanoseconds' worth of processing - but it's still time wasted.
Also, keep your desktop wallpaper simple. It'll save you time when trying to locate that file or folder tucked away in a crevice of the Grand Canyon. Enjoy.