Well, it looks like I have survived all of my final papers. All that's left is a history exam (Monday), my German oral final (today), and my Greek drama final (Tuesday), and those shouldn't too horrible, I'd expect. In the mean time, there's D&D to discuss!
In the end, I've decided to go with a more traditional campaign structure. While I like my Barsoomian sword and sorcerery idea, it just isn't fitting for first-time players. The real question now is whether to go the megadungeon route or something more akin to the West Marches experiment where the characters move from location to location at their own whim.
While the megadungeon would be much easier for me to set up and is much easier to run, I think I could do alright with a more wilderness oriented game. The real question is what would be more fun for everyone to play. I do have a couple different ideas for potential megadungeons, but much of it feels more like a bunch of micro-dungeons slammed together and interconnected - i.e. very easy to split up.
Whether I go OD&D or AD&D will depend very much on this choice. To me, AD&D seems to fit better with wilderness and city adventures, while OD&D makes me think more of dungeoneeriong. The AD&D class set-up just fall more in line with those types of adventures - druid & rangers for wilderness, thieves & assassins fit well in urban areas. I guess AD&D just appears more mideival and less pulpy in my imagination.
As of right now, I'm actually leaning towards the West Marches route, feeling inspired by this hex-map posted on the newly fashinoed From Beyond the Drowning Woods blog. If you haven't checked it out yet, you totally should.
Anyway, I'm rambling and should probably be getting ready for class. Hopefully I'll have something worked out by the end of the evening.