All three books are different
Sirmarilion, or Hobbit and Lord of the Rings saga - each is in other type.
Sirmarilion - mithology of Middlearth is something were dry and unpleasend to read, ( i think you should read this later - first hobbit then Sirmarilion and then Lord of the Ring - its best solution)
Hobbit is a funny story, sometimes dark but very light and everyone can read this, short and like a fairy tale 
Lord of the Rings is different, very long and sometimes maybe boring - it depend who is reading…i think this is briliant book, just briliant!Ive cried when i finished it!!REALLY 
( boys dont cry i know but i was 14 )
I remeber when i read about that Peter Jackson is working on movie - adaptation!I was very happy about that fact!Now im waiting for another, HOBBIT ..i wish i see this movie soon :)…so Peter get to WORK !!