This jam is intended to be super-casual and friendly to folks with neither coding nor game jam experience.
Twine is a graphical tool that anyone can learn in just a few minutes: Twine games tend to be like the old "Choose Your Own Adventure" books, and once you learn the basics, it's easy enough to add graphics, sound, simple animations, and RPG mechanics to them.
Twine is free and open-source, and anything you create in Twine is 100% your own property. You can download Twine, or use it online, here:
http://twinery.org/
(I recommend the download version - if you use the online version, you work is saved in your browser's local files, and can easily be deleted without you even knowing.)