You need to use the file system browser, Nautilus depending
on which Ubuntu you are using, I use Xubuntu 12.04. On my
system there is an icon named "File System" a double click
brings up the a view of all the file systems and directories
on your PC. You should be able to see the mountable file
systems and you can double click on them and they will be
mounted and you can explore them. Once you drill down to your
pictures/music you can copy files to your Ubuntu home directory.