It opened with discussions of why monsters. And how the original monsters were portents -- deformed births to man or animal. (Didn't get into the fact that other monsters were other anomolies. A comet was a monster.) This was while heroes went out and fought creatures that we would now call monsters.
Well, the Nemean lion was not a monster -- just a really tough lion -- but a chimera, for instance, is.
Why do people go and invent monsters? To frighten people off from doing something dangerous? But why not go into the real dangers? There really were wolves and saber-toothed tigers out there. Little Red Riding Hood -- but wolves aren't really that dangerous to humans most of the time. (What didn't get mentioned that was in the folklore versions, it's often a werewolf.) The point that many of the dangers are less dramatic, like breaking your leg, and really, they didn't know that there weren't monsters out there.
Brushed on how believed in monsters are different, but didn't get in depth on it.
How a monster contains a problem in a finite, determinate, and even perhaps mortal package. One audience member talked of how his daughter loved Bigfoot and could explain away things like no bodies by their burying the dead -- but not how to handle roadkill. A quip was made about how girls want to ride dragons, and boys to be dinosaurs.
The cleaning up of the vampire from legend. Stoker wasn't entirely to blame for that. Dracula was an anomolous vampire, most were mindless, and even he was not exactly sparkling. Meanwhile, zombies were pushed into the mindless dead killer slot. (What didn't come up was that zombies were not originally monsterous. They weren't a danger to the living, except as a warning of future possibility: becoming one and so not being able to escape slavery even in death.)
The monster with a mind, like Frankenstein's, needs an origin story, but can still end up monstrous. Then, there are monsters which are more like a force of nature.
One panelist thinks the nastiest one is a a monster in Gene Wolfe, a bear that eats people and retains their minds, so you can talk to your dead grandfather -- its best trick is to come to the door and ask you to come out in the right voice. I brought up the Cybugs from Wreck-It Ralph, and asked about many monsters and whether they work -- I think they really work only as a force of nature. One panelist brought up orcs, who never get a point of view except in Mary Gentle's Grunts (his observation, not mine). Others brought up giants and ogres. (Without bringing up that you seldom get a whole bunch of them in a story.)