Hi @ChesHatter
dont know if you have started playing already or not., but:
I first purchased TW2 on Xbox 360 back when I didnt have a PC to play TW1 on. I started the game and very quickly found that this was a deep game, with huge lore, and realized that what made it so great was the sourcel material (the books) it drew on. In chapter 2 of TW2 I decided to stop playing, go back and read the books, then plau TW1 (I now have a PC) and then play TW2 and by then TW3 will be available and probably cheaper.

I just started reading the book before last in the series. They are a must read. I can't wait to finish them and start the game, but since they are so good, I don't want them to end. they are just that good. The last major series I read was Song of Ice and Fire, and the Witcher books are at least as good. I can't wait to see how CDprojek built on the novels. I know from playing TW2 that they did an astounding job of fleshing out the world and putting it into video game context.

I would highly recommend reading all the books first, then delving into the games.

since there are no official English translations for the whole series, I decided to read it in Spanish (official translation for all the books). The Spanish translations are excellent and really worth the read, albeit a difficult read since there is a huge amount of medieval jargon and vocabulary. But if you don't dominate Spanish enough to read the official translations, there are English community translation whhich a friend of mine is reading now, and who said feel as decent as any other official translation.

If you do decide to read the books, I do suggest you compliment the read with the maps provided along with the games, you can find them in the extra files in PDF format, they will help you understand and shape the geography and politics of the world.

In any case, enjoy, the games, enjoy the world of the witcher, they deserve the recognition they are already getting, and more.

Community translations are available here: http://forums.cdprojektred.com/threads/16494-Our-Community-Fan-Translations

Spanish translation is one of the best, and unfortunately English one (at least official) isn't as good. Often community translations are even better than the "official" one.

Details on the books (the sequence and etc.): http://witcher.gamepedia.com/Witcher_series

Start with the game. Books are VERY awesome, but you do not need to read a single line from them, in order to understand everything while playing the game. Some game events though, that happen only by being briefly mentioned from NPCs to Geralt, are entire book, or chapters from book, stories. example: You had a dragon friend once actually, so the joke's on you.

Keep in mind, though, Geralt is certainly NOT a saint (anything but, actually), yet he has something noble about him, like helping the weak and those in need, having compassion, like refraining from killing intelligent beings, and generally preferring to lift a curse and solve a problem, instead of cutting down through, trying to find out what happened later. Although this shouldn't affect your in game choices, keep it in the back corner of your mind. Especially if you want a "roleplaying" playthrough...