If you want to get a Microsoft certification under your belt then if you register here, take the exam before January 30, 2008 and heaven forbid, not pass then you are entitled to retake the exam again for FREE.
Having done a few Microsoft exams I know that some can be quite tricky. It generally isn't that you don't know the material, it is that you don't know exactly how Microsoft wants the questions answered. My advice is that if you are unsure then try and examine the question again from Microsoft's perspective (ie which option requires the implementation of more Microsoft software?).
Now with this free double shot you should have no problems getting through, even if it takes two goes!