Use the "Disks" app.
Load the Disks app (In System) and select the disk with the filesystem you want to mount on startup.
Then select the filesystem on that disk and click on the gears (for configuration).
Select "Edit Mount Options" from the popup menu.
On the setup options, click to check the "Mount on Startup" box. (This will add the entry to fstab when you click on "OK").
Reboot, and your filesystem should be available.
I agree with other comments here regarding manually adding lines to fstab via CLI/text editor. If you take the time to look at your fstab file it will help you understand what changes have been made and, ultimately the CLI method will become faster for you.
1 - Write down the UUID of the drive that you want to mount by executing the following command:
2 - Then edit the fstab:
sudo gedit /etc/fstab
3 - Add at the end of the file fstab:
UUID=D638F77338F7514B /media/baraldi/win_www ntfs defaults 0 0
Be sure the UUID matches what you recorded in the first step
4 - Restart
That is all. Good Luck.