Day 1: Favourite Season
Oh, tough one. I love, love, love a lot of episodes S4 but overall the season isn't completely satisfactory so it's between S2 and S3. And I can't remember what I chose before so it must be close!
It's S2 because "Some Assembly Required", "Reptile Boy", "Bad Eggs" and "Go Fish" are still better than "Dead Man's Party" and "Beauty and the Beasts".
ETA: the last time I did this I did say it was S4. Oops.