Minas Tirith, Minas Morgul, Helms Deep, Isengard and Barad Dur.
There is the elvish language, then the dwarven language, not to mention the runes or moon letters.
Hobbits come of age at 33.
Speak, friend, and enter. It was of course in an elvish writing but that is what it means in English. The complete inscription read: "Ennyn Durin Aran Moria. Pedo mellon a minno.
Im Narvi hain echant. Celebrimbor o Eregion teithant i-thiw hin" The Doors of Durin, Lord of Moria. Speak, friend, and enter. I, Narvi, made them. Celebrimbor of Hollin drew these signs.
Try here for a start: [http://en.wikipedia.org/wiki/Balrog]. You can also read about them in the older stories of Tolkien (Silmarillion, and those in the HoMe).