By default backgrounds are handled by Nitrogen Accessed through the menu under Preferences –> choose wallpaper. Bundled wallpapers are stored in ~/images/wallpapers/shared/backgrounds although you can add your own to ~/images/wallpapers/shared and they will automatically show up in the Nitrogen selection menu.
By default Icons aren't shown on the desktop although PCManFM can be configured to handle icons and wallpaper by going to Edit –> Preferences, then selecting the Desktop tag and ticking 'Manage the desktop and show icon files', and optionally 'wallpaper'. The 'Show menus provided by WM when desktop is clicked' is needed to allow you to right click on the desktop to bring up the main menu.
Desktop path can be modified in ~/.config/user-dirs.dirs for example, change XDG_DESKTOP_DIR=“$HOME” to XDG_DESKTOP_DIR=“$HOME/Desktop”
More options for adding icons to your desktop can be found here.
One option is this script for a wallpaper slide show, preliminary instructions are here. For instructions on downloading and installing scripts look here and for instructions on adding it to your autostart folder look here.
To use Terminator as your background follow this howto.