As a DM which do you like best?

[HellHound]

None of the above.

As a DM, above all I like playing the game.

 

[Herobizkit]

I enjoy NPC creation best of all. I run mostly solo campaigns so the "supporting cast" and "extras" have to be well thought-out and significant. Person-to-person interaction is far more exciting to DM than leading monsters to their doom.