I bought Lightroom and Capture NX2. After using both, I uninstalled Lightroom. Lightroom is a good sorting program but it doesn't store the information (ratings, crops, changes, etc.) in the RAW file so it's not visible in Capture NX2. If you need to do advanced editing, you need Capture NX2 or Photoshop. I prefer Capture NX2. ViewNX2 and CaptureNX2 make a good combination.
Whichever you chose, I recommend staying with the same vendor for the sorting application and editing application (View NX2 / Capture NX2 or Lightroom and Photoshop).