Subs: sealed vs. ported

I need to add a sub. I don't have one now, so I'm not replacing anything, and I also don't have much in the way of preconceived notions. My reading is making me think sealed is preferred for music/2.1 channels, and ported is preferred for movies. Is this a fair assessment. I know everyone will have their own preferences for brands/models, and I'm open to suggestions, but it seems my first decision should be sealed or ported (or one of the brands that has ports and comes with plugs?)