Thorin Oakenshield got the name "Oakenshield" in the Battle of Azanulbizar, when he was disarmed he picked up an oak branch and used it as both weapon and shield.
Shadowfax (seen above with Gandalf barring the gates of Minas Tirith when the Lord of the Nazgul tried to enter in) was a prince of the Meras, unusually swift horses that (until Gandalf) carried only the kings and princes of Rohan. Shadowfax was one of the few horses able to outrun the horses of the Nazgul.
Hobbits could only average about 24 miles a day. Though there were exeptions in the Lord of the Rings, usually when Orcs or the Nazgul were involved, that was the average distance.
After Eowyn named Meriadoc Brandybuck a Rider of Rohan, he was given the name Holdwine in Rohan.
There were originally 5 of the Istari or Wizards, Olorin (Gandalf), Alatar and Pallando (the blue wizards), Radagast and Saruman (Curunir).
The characters that have the three Elven Rings are Gandalf (Narya, The Ring of Fire), Elrond (Vilya, The Ring of Air) and Galadriel (Nenya, The Ring of Water)
Aragorn and Arwen's marriage was one of three known marriages between Men and Elves. The other two were Tuor and Idril, and Luthien and Beren.
Pippin was the one who was always getting in trouble, but if it wern't for him, there would have been a lot more important deaths, such as that of Faramir, Capitan of the Guard of the Citadel.
Gollum was a Stoor hobbit, dating from when the Stoors were living by the banks of the Gladden Fields.
Dain Ironfoot, though young in the reckoning of the Dwarves, was the one to slay Azog, the Goblin. Azog was the father of Bolg, who was slain in the Battle of the Five Armies, in which Bilbo had a part (See the book The Hobbit)
Aragorn was counted as the last king of the Elder Days and was given the gift to lay down his life of his own free will, as the Numenoreans had in the early Second Age of the Sun.
Gandalf was made a Lord of the Mark after his healing of Theoden. At this time he was given Shadowfax