I went with All Good Things with BOBW a close second. AGT was the perfect TNG episode for. BOBW had some slow parts and questionable battle scenes (a lot of sitting right in front of the cube when they should have hauled butt). Chain of Command was really good.
Time's Arrow was the worst by far of the bunch.
Time's Arrow isn't the best two-parter, but it's my personal favorite of the series. Every Trek series has done an episode where they travel back to modern times on Earth, and this was the best of those.