There are a bazillion editions. If you're only going to get one, find a nice, illustrated hardcover (the centenary edition with Alan Lee's art is nice), or the Red "leatherbound" in a slip-case. I think the all-in-one is just easier.
I collect, so have many many of both hard and paper cover, single volume or trilogy sets.....Peruse through what is out there at the Tolkien Library on-line....they show many different editions, and you can at least get an idea of how much more difficult choosing just one will be...
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.