Before Frodo, Pippin, Merry, or Sam even existed, he knew of the Ring. For he was there the day that the evil of the One should have ended.
When Isildur cut the Ring for Sauron's hand, Elrond lead Isildur to the heart of Mount Doom, to the one place where the Ring could be destroyed...
"Cast it into the fire!....Destory it!"
"No," Isildur had replied with a smirk.
"It should have ended that day..."
But it did not, and now the lives of Middle-Earth are in a greater danger than they would have been if Isildur had destroyed the One like he was instructed by Master Elrond to do.
MORE SOON....
PLEASE BE PATIENT.....