Those are your guy's favorites?? I dunno if I could choose just one but the very first Halloween episode is the one that made the show really solidify itself as something great. Honestly though, the best things on Community IMO are in the dialogue. That's always the best moments and when some of the funniest stuff has happened. One of my favorite moments still to this day is when they're trying to teach Abed how to pick up chicks in season one and Troy starts referencing Calvin and Hobbes "You could be like a Calvin! His best friend was a tiger, he always went on dope adventures and if anything ever got in his way he just pees on it" just the way Glover delivered that line killed me and its stuck with me every since