Install the package caja-share and restart caja (or log out, then in). This enables the "Sharing Options" when you right-click a folder.
From a terminal: (CTRL+ALT+T)
sudo apt-get install caja-share
killall caja
caja
Now, when you right-click a folder, you'll have the option for "Sharing Options".
Here you can configure a network share that can be accessed from other Windows computers.
