Well, you found fstab
There should be a line like this for each NTFS partition
/dev/sda1 /media/sda1 ntfs defaults,umask=007,gid=46 0 1
Of course you have to adjust to whatever your disks are called
When you do this it's the equivalent of working with disk management in Win XP but there it's a graphical environment with tons of limitations - ever tried to reuse a drive letter?
And of course editing fstab needs sudo
gksudo gedit /etc/fstab
Make a copy first - simplest way is to just open fstab and copy all into a file that can be on you desktop.
Don't fix it if it ain't broken, don't break it if you can't fix it