You Can't remove the pre-installed icons. But you can drag them into groups (for the most part).
Simply drag one of the icons you want to hide on top of another icon you want to hide. Name the new icon folder (something like "other stuff").
Continue to drag icons on top of this new folder until the icons you don't normally used are all continued in this one folder.
Hold down the Volume Down and Power button.
This will be stored in your Pictures\Screenshots folder.