havent tried cs6 yet, but is there a general or standard 1080 24p, thats what I would go with. Cause when you output, your better off converting to square pixels 1080 24p. At least thats what I always do in cs5.5.
You are missing the presets:
Start Premiere Pro. Create a new project and new sequence. Close Premiere Pro. Restart.
See if that will bring back the presets.