What, in your opinion, is black's best opening after 1.d4, and if you could own only 2 books explaining that opening, what would they be?

1.d5, and the only book i'd have would be Chris Ward - unusual queens gambit declined - if you learn it and understand it, it will catch most players off guard

As with all reasonable openings, there is no best response, except that ...d5 and ...Nf6 seem soundest, and is where most queen pawn openings come from. I like the Benoni and King's Indian because they turn the game into an often intense battle with winning chances for both sides, so that's my opinion.

i like the slav with the pawn snatching ideas! 1d4 d5 2 c4 c6 3... dxc4!

There are many replies to D4.Example: D5 or D6..Depending on your style of play...C6? My favorite books : Fireside Chess and Pawn Power....

1...Nf6 intending the Nimzo-Indian is my favorite reply.

The Albins  Counter Atack, dose me grand!

Benko Gambit!

I suggest getting Andrew Martin's Benko Gambit DVD from chessbase, as well as Yelena Dembo's "Fighting the Anti-King's Indians" in case white doesn't play mainline stuff.

Hmm.. I would opt 1..Nf6 heading into either the budapest defence or KID. Both are fighting openings which gurantee you some attacking chances. The 2 books I would recommend are the 'fabulous budapest gambit'by viktor moskalenko and starting out: KID (everyman series) by joe gallagher.

The 'chigorin defence according to morozovich' and any book showing you how to play albin's counter gambit is very useful @ club level against 1.d4 as well.

Hope this info helps!

2.d5.

1...d5 2. c4 c6 (slav defense)

best book for openings i've read is by fine - the ideas behind chess openings. great book.

Does no one like 1... f5 ? The Stonewall Dutch always gives me a fun game.

I used to be really interested in it, but not anymore because it's much less flexible than the KID, and the stonewall's hole on e5 is just too much for me to tolerate. White stands better because he doesn't really have any positional problems but black has to put up with them to get some chances. The KID and Benoni don't have many weaknesses so I can usually focus on my ideas.

yes, I like 1. ... f5

My personal favorite reply is 1...F5, the dutch defense.