You know, I have to confess that the LotR edition I use most often these days is the pdf one I keep on my computer desktop. Very handy for searching...
The first Tolkien book I ever saw, when I was small, was this one:
http://www.tolkienbooks.net/html/the...937-1984_5.htm - it belonged to my mother, I think it's still around somewhere, without its cover probably.
We also had in the house the Pauline Baynes single volume paperback Child mentioned, although it lost its cover very quickly due to the multiple readings it endured...
The edition I love the most is my first edition copy of the Silmarillion, bought with my very own saved-up pocket money from a little bookshop which is now, I believe, a Subway sandwich joint....