If you find Recent Files in Cinnamon menu is annoying, then disable it. Unfortunately, Cinnamon System Settings has no option for this tweak yet. So you must do that manually. I use Cinnamon 2.2.13 on Linux Mint 17. This tweak is applicable to Cinnamon in another Linux distro.
Open menu > Recent Files > press Clear list. If you open another files in Cinnamon, this section will be filled again.
To disable this Recent Files permanently, we need to set the recently-used.xbel file to immutable. It means no one can edit this file, create link from, delete, add a text, except a root remove the immutable attribute from this file. Perform this command:
sudo chattr +i ~/.local/share/recently-used.xbelchattr is change attribute command. Option +i plus immutable) gives immutable attribute to the file. That ~/.local/share/recently-used.xbel is the file where any recent files recorder for Cinnamon menu. Remember that you can't perform chattr command in a livecd (RAM filesystem).
To revert it back someday, as a root, perform a reverse command:
sudo chattr -i ~/.local/share/recently-used.xbel