Not able to access "shared" partitions - ownership problem
 

Using Gparted I created 2 primary partitions and 1 extended partition. The extended partition contained 4 partitions: swap, /home, shared (anything I want to be able to access from any user), ISO (for keeping ISO that I might want to run in VB or burn to CDs). Then I installed Ubuntu on the first partition and LinuxMint on the second. They both share the swap and users from both OS's were able to create/use their home folders. But my problem is that no user from either OS can copy/save/move anything to the "shared" or "ISO" partitions due to those partitions being owned by "root". Maybe I should not have created those last two partitions until after I installed the two OSs?

I have been shown how I can copy files to those partition by using the terminal. But that takes an extra process and I would like to allow any user (from either OS) to be able to copy/save/move to either of those folders. I have read that it's proabably a matter of "changing ownership: chown", but new to the terminal and commands, I'm not so sure what the command line should say. Thanks, John

It may be overkill, but opening gnome-terminal and entering the following: (replacing <mountpoint> with the actual mount point of the affected partitions) and remountingthose partitions should do the trick.

What does the /etc/fstab line for the ISO partition/filesystem look like? Does it differ from the others?

Perhaps the problem is not the file system but the files/directories themselves. What are those ownerships and permissions?