For reading, I would recommend picking up the thicker TPBs called Showcase Presents.
While all of these are great, I love the Unknown Soldier and Enemy Ace books. The War That Time Forgot book got me to really enjoy the Dinos. Sgt. Rock is a no brainer and the Haunted Tank stories are all great too.
See the pics below. For $10-20 each, you cannot go wrong.
That is a nice stack of reading material.
In addition to the b/w Showcase editions, there is also color DC Archive Editions for Sgt. Rock vol. 1-4 and Enemy Ace vol. 1-2. Though they are a bit more expensive due to being out of print.
I've noticed DC is starting to put out a lot of Golden Age and Silver Age omnibus editions. Hopefully we will get some DC War ones.