I think there are several ways to fix this. It all depends on what you want to see, and if you are completely comfortable in the terminal. Rather than worry about changing ownership, I'll just cover changing permissions. (Although the other way is actually faster.)
Fast and dirty permissions method:
Mount the drive graphically.
Then, in a terminal ...
(provide the root password)
(Note the name of your mounted drive)
chmod 777 -R (here give the name of your mounted drive)
(If you really want to watch all the bloodshed, add -v after the -R.)
To do this graphically:
(You'll still need the terminal here to get a root browser.)
(give the root password)
use that browser window to surf to the /media directory, and then right click the mounted drive and use the GUI tools to change permissions recursively
to read & write for all users.
I hope I haven't forgotten anything here, but if I did, I'm very sure someone will be all too happy to call me down on it. (Normally, I just grope around until I accidentally land on the correct syntax.) <..