short answer: "neither - find a COM you can get without hyphens"
Long answer:
I try to avoid hyphens, unless it's to cover off a non-hyphenated version I already own. I think they have SEO usefulness perhaps, but that is more than offset by the amount of traffic it will lose to the non hyphenated name.
Dot orgs would be appropriate for certain types of content more than others - depending on the intended use, it may make more sense to reg the INFO or NET or even something like CC or TV...
It depends on the content really - if you're plannning to develop, the quality of content will be a bigger deal than the name in making the site a winner. regardless, my first choice would still be a COM. Can you find a suitable com at sedo or afternic or ???.