As on all momentous occasions in life, we find ourselves reflective and nostalgic as the Glee season-one finale fast approaches. So much was great: singing Puck! Kurt and Mercedes as cheerleaders! Jonathan Groff, all too briefly! And then, well, even we must admit there were duds — anyone remember “Hairography” and the mash-ups that should never have been? As we prepare for season two — when Glee will be high on success and either pleasantly surprise us or, egads, go off the rails — we took a look back on what Ryan Murphy and Co. have done exceptionally well, and which songs would have been better left unsung. Let the arguments begin!