And when you have finished with the KJV or NIV or whichever you chose, head on over to the Lolcat Bible Translation Project at
Same crap, but reads much better.
My first recommendation would be the New Revised Standard with a decent commentary in hand. My second recommendation would be a copy of the New American Standard with a decent commentary. Both cling relatively close to a literal translation, though the NRSV in my experience tends to be more readable and less likely to cause the reader to throw it against the wall and thus more likely to see you through.
HarperCollins' study bible with Apocrypha or the New Oxford Annotated would be ideal, and can both be gotten CHEAP (like $2.00) used. Both the HC and Oxford Study Bible provided a lot more context for the individual books, including timelines, maps, and historical-critical analyses that are necessary in understanding what the authors might have intended, while decidedly staying away from an evangelistic focus. I can honestly say you'll understand the Bible and its background better than most Christians with one of those two texts.
KJV lies third, though as many people have pointed out it still has cultural value and a very strong following within the church.
No matter what, I'd suggest a decent commentary or dictionary - don't buy a concordance unless you actually plan to learn Greek and Hebrew. If you live in a town with a decent (or Bible) college, the Anchor Bible commentary and reference series show a compendium of the best scholarship available. If not, the Anchor Bible Dictionary, which "includes articles on the Dead Sea Scrolls, early Jewish-Christian relations, the historical Jesus, sociological and literary methods of biblical criticism, feminist hermeneutics, and numerous entries on archaeological sites, as well as bibliographies with citations listed individually at the end of each article" is available on CD.
A lot of good advice here. It really depends on who your 'target' is, who you have in mind when you're arguing.
If you have a particular denomination or related set of denominations then you're best served getting one of the translations that they use. So if you're trying to target evangelical christians, you should get the ESV or NIV. The NIV is also a good choice generally in terms of being familiar to North American christians. In any event, it's easy to call or visit a church and find out what the pew bible is for them.
If you really want to play it safe however, the KJV is the best option. While all translations have their detractors, in terms of avoiding debates over the translation you chose...KJV will take you the further with more denominations than any other.
Lastly if you can get a study bible or annotated bible - do. Having more information about the bible and the beliefs of christians can only help your position. Having such a resource is invaluable because it means you can get the sophisticated interpretations up-front and thus be well prepared. I don't know if your argumentation style involves being able to beat people on their own turf...but if it is, study bibles will help you greatly in that task. If you'll be engaging with serious catholics it would be prudent to get a version that includes the apocrypha.
Whatever version you decide to get, you might want to consider also taking a look at the NET [new english translation] bible online. It's freely available and they do a good job of explaining their translation decisions. That resource will provide you with a good insight into the translations choices that have to be made...and it won't cost you any money.
Here, for funsies this is a good one.
Quite fun to try to get through without laughing.
the Skeptic's Annotated Bible is my favorite. I don't know if it is available in other formats though. It is still a great place to go to drop piles of quotes that violate science, are inconsistent, or are unjust.
I realize I am a little late on this post, but I figured that even if you have already decided on a Bible then at least maybe something I share may be helpful in some way. A couple things:
1) If you are looking to just have a reference resource at your disposal for debating and such, then I would say use a website like www.biblegateway.com or www.blueletterbible.com as these sites offer excellent search functions and have just about any translation that you might need. I prefer biblegateway personally. They would would also be good sites to compare the various translations for any hard or digital copies you may decide to invest in.
2) What you should know about translations and error. You may already know a lot of this, but i will share anyways. The O.T. is written in Hebrew and Chaldee and the N.T. is in Greek. The problem with translations is that when translators make their translations (KJV, NKJV, NIV, NASB, YLT, etc etc) the products lie on a spectrum of interpretation from literal to paraphrased.
The more literal the translation, the more accurate it will be though some people don't like these cause they tend to be harder to read and the "all-knowing" heads of theology seem to think the subtle cultural references and such will be lost on the average reader. Thus there tends to be a stronger push to the other end of the translation spectrum - paraphrase.
The problem with the paraphrase is that these Bibles are translated in a way that leaves the meaning of a text solely in the hands of the translator. They read the test, decided what it means and then put this in english...thus the reader is forced to succumb to the translators own theological bias and agendas consciously or subconsciously.
A quick example it the word "hell". The concept of hell as taught by the western church is not of Jewish origin. It is not in the Jewish scriptures and Jesus taught from the Jewish scriptures, therefor, he did not teach "hell" as an afterlife of eternal torment like the church says he did. So, if we look at translations, the most literal translation that we have "Young's Literal Translation" doesn't contain the word "hell" in it at all while one of the least literal "King James Version" contains it 54 times. (I would love to go into more detail regarding this particular word study if anyone is interested...maybe I'll start a thread on it soon :)
So, the point is, if you want the least amount of bias, I would go with the more literal translation. Young's Literal Translation is the best, they ascribe one english word to the closest Hebrew or greek equivalent and use it in a 1:1 ration no matter how it sounds. The trade off it that the wording can be a little funny sometimes, but anyone who does well in reading and english should be fine.
I would also look at the New American Standard Version if the Young's is a little too tough to read. The NASB is prob about the second most literal and is a much easier read.
A comment or two about other translations:
NIV - Widely popular esp among evangelical christians, but very inaccurate and full of western christianity doctrine. This is a very easy read and is great if you want to develop the same perspective on doctrine and teachings that most of the US has, however, you will most probably miss the truer deeper meanings. And with the truth of the texts in hand, you can take on anyone.
KJV - I love this translation for leisurely reading, it is elegant and flows well, however, the translation is soo inaccurate (as even admitted in the margins in many places by the translators) that I would not ever recommend this for serious study. The only usefulness as a study tool is that it goes hand-in-hand with Strong's Exhaustive Concordance which is a must-have for any seriously studying the bible. Also, it is considered by older more fundamental christians as the only one "true" translation and of course this is IMO, crap.
As far as the study bibles that have been mentioned that also have historical notes would be a great idea. Parallel bibles are cool, but I would pick maybe a study bible that is just one translation to start.
Also, if you want an awesome unbiased source of instruction on the history and accuracy of scripture, check out some of this guy's books: Bart D. Ehrman He is a doctorate professor at Harvard, if I remember correctly, and he set out to learn greek and hebrew so that he could study teh scriptures for himself. He offers such an excellent and unbiased perspective that even seen books written like this one which are written by dogmatic Christians who have had their foundational beliefs rocked by the awesomeness of Ehrman's critical and frank analytical study of the scriptures.
As far as reading the scripture, definitely start in the New Testament and read is in order from Matthew onward. The Old Testament is a little tougher but after the New Testament, I would go back to genesis and just read in order from there. That is what I did and it worked really well for me. I actually used the NASB, for that study and now use that one and the YLT for my study.
After all of that, if you want to go even deeper, I would suggest delving into the Dead Sea Scroll collection and even the Nag Hammadi library. Very interesting to compare those to what we see in the canonized bible and especially when we allow seek Ehrman's tutelage regarding scripture and church history. I am very tempted to suggest that you read some of Ehrman's stuff first so you have a really good idea on the origin and the context of the scripture before you actually read it...I think that might be most beneficial to you, but that is just a suggestion.
So, 1) Understand the history, 2) study the texts in the Bible (literal translation) and use a concordance to reference back to the greek and hebrew 3) Read the extra-biblical scriptures (Dead Sea, Nag Hammadi) and 4) stand tall in your equipping being very confident that you will be ready to take on even the most learned christian apologists and/or anyone for that matter :)
My $0.02 :)