Here's how you can make Nemo your default file manager in Ubuntu 13.10. If you don't have Nemo installed already, you can get instructions here.
1. Open a terminal window.
2. Type in the following commands then hit Enter after each.
xdg-mime default nemo.desktop inode/directory application/x-gnome-saved-search
gsettings set org.gnome.desktop.background show-desktop-icons false
gsettings set org.nemo.desktop show-desktop-icons true
Nemo is a complete fork of Nautilus and its goal is to extend the Cinnamon user experience to desktop and file management.More at Noobs Lab