One of the first decisions to make when considering how to develop your content on a CD/DVD is that of your audience: what are their needs and, more importantly, what are their capabilities.
Some questions to ask:
What computer speed is your audience likely to have?
What CD Drive speed is your audience likely to have?
What level of complexity is your audience likely to be comfortable with?
Should the CD/DVD automatically run?
Should the CD/DVD be downloadable to run off of the users hard drive?
Does the CD/DVD need to be protected or encrypted?
Does the CD/DVD need to be developed in multiple languages?