Hiya.
I'm pretty much a 50/50 DM. I don't need much in the way of descriptive stuff, detailed NPC's or plot lines. I like to have random encounter tables, maps (LOTS of maps!), and bare-bones room descriptions like this:
"Room #11 - The Study. (dusty, ragged tapestries, candle stubs, cobwebs, cool breeze whistles through broken windows; lost of mean rats that attack if attacked themselves first, lead by three giant rats; magic scroll hidden somewhere)."
That's all I need. I can "wing" everything else as needed. This way, if players are in room #10, next door, I at least have some info about what may be in there...like a small hole in the wall that rats run through, maybe the PC's can hear the whistling air from room 11 if they listen closely, perhaps there is a stack of books on a table in this room, 'borrowed' from the Study, etc. In short, I like just enough info that, at a glance, I can let my imagination run to fill in the blanks. I can tone stuff down if the players need a break from mechanics, or I can bump things up a notch if they are itching for a fight, or I can play on their fears if they seem to be getting into the 'spooky atmosphere' of the abandoned mansion, etc. The modules with write ups of every little thing in the room, a page of monster stats, and another half page of "what will happen..." crap is useless to me. You know, the "
Fellworth will first cast Mage Armor, then he will agitate the rats, if he has time he will...etc...etc...etc"; and, a half page later, his write up is done. It is at this time that the PC's use Wizard Eye, spy on him, then sneak around to the back room and use Passwall to open up the wall behind him where the thief tosses a Rope of Entanglement on him so they can question him. ... ...and that half-page of "tactics" goes out the window. Wast. Of. Space.
So...yeah, "winging it with point form inspirational notes" is how I roll.
^_^
Paul L. Ming