Such a question! My answer is that it depends. I love them both in the right circumstances and associate both with Christmas.
Egg Nog if it isn’t homemade. I like the dairy pasteurized stuff, especially from Broguiere’s Dairy (Oh My God so good!). I also like the egg nog latte they serve at coffee places this time of year, especially if they do half milk, half nog. Homemade egg nog (with or without booze) is a no go for me. I wish it were otherwise because I’d love to be able to make some sugar free, but such is life.
The only hot chocolate I’d have over a well-made latte is homemade Mexican hot chocolate. For those of you that haven’t tried it, Mexican chocolate comes in cake and is flavored with almonds, cinnamon. I make hot chocolate by breaking off the right amount of cake, grating it, and then heating the grated chocolate in whole milk over a medium heat burner. Once the chocolate is mostly dissolved and the milk is hot (not boiling), I pour it into the blender with a little pinch of chile powder and blend for 10 seconds or so until foamy. Fit for an Aztec king!