Neither are particularly my genre of interest. I like some romantic comedies, and some action films, but I think in general I would go for an action film because they can meld into other genres more easily.
I like both equally, so it really depends on my mood. Some nights I'm craving a good comedy, and it seems the decent being made now are romantic comedies. Other nights I crave a good action flick. It's all about my mood ;)
A combination of both can be fun, like Date Night, or One for the Money. Given a choice between the two though, I mostly prefer action. My partner's just as happy to watch a rom com with me if that's what we're in the mood for, but it's more likely to be a foreign one like Hors de Prix (Priceless) or Amelie than a Hollywood one.