Click on 'Places' at the top left of the screen and your second HD
should show in the list underneath the 'Computer' entry with the name
that it was given when formatted originally. Click on it to mount and
view the contents then you can copy/past to and fro all you want :-)

Useful tip - when you have the drive content showing ( or anything
else being viewed in the file manager ) if you Right Click on a folder
or any item in the folder list on the left you get an 'Open in a new
tab' option .... yes, file manager has tabs just like a browser !!

Ubuntu doesn't automatically mount permanently installed HD's
unless you tell it to do so ( either using the mount manager in 'Disc
Utility' or adding manually from the command line ), or has
added this functionality.