Having a keyword heavy domain name or one that is catchy?

Which choice do you think is usually better?

For instance, free-teen-videos.com VS. teenworld.com

This has worked for me in the past, but you don't want to make the name too long. I don't think -'s matter from an seo perspective, but they do make the domain easier to read, which might help your clicj through rates.

Looking at your examples though, I prefer teenworld.com. if I were google I would penalize domains with free in the url! lol

There is currently some debate going on with the dashes. Ultimately I think having your keywords in the domain is key.

teenworld is brandable - so you have to consider, do you want to promote a brand?

I personally would buy them both, start with the keyword rich site/domain and use it for blogging, and then point that to your branded site. Just one of a million long term scenarios you can consider.