Deities & Demigods doesn't seem like a terribly good fit based on your needs. As others have noted, it doesn't have much in the way of background info, as it is essentially an MM for deities; it also doesn't stack up well with the ELH.
Faiths & Pantheons is certainly more interesting, and has more utility in a fantasy setting than the Earth-based pantheons featured in De&De (Greyhawk being the exception). It is FR specific, but if you're only going to mine it for ideas that shouldn't matter too much.
The Divine and the Defeated -- the Scarred Lands god book -- is also quite good. It includes stats (and they don't mesh with De&De, or with the ELH for that matter), but it also has a lot of flavor and background material. Depending on the nature of your homebrew, it might be more or less useful than F&P -- the Scarred Lands has a feel all its own, and it diverges a lot from "standard" fantasy. Even though I don't plan on using it, I found it to be a thoroughly enjoyable read.
Book of the Righteous is probably your best bet: no stats and a
ton of background info, all wrapped up in a beautiful and well thought-out package. The only area it fell short for me was in its lack of options for evil/villainous deities -- a staple of most fantasy campaigns, IMO. Everything in it ties together very well, however, and you can probably dovetail in details from other sources to cover the dark side.
Hope this helps.
