the poster above is pretty spot on. Forced marriage 100% should be illigal, but arranged marriage? as long as its consensual, then why not?
Obviously the hard bit is proving consent, but I don't think we can ever do better then just asking people.
There is a good bit of evidence to suggest that arranged marriages work quite well. I remember reading a study a while back that showed that on average a persons parents are better at picking long-term partners then the person themselves. Which makes sense, on average your parents know you better than anyone, and they are not clouded by lust/romance, so rationally they would be able to make a decent suggestion.
Obviously its completly against the way western culture is these days, and its not practical to have your parents arranging things for you if your not part of a specific culture that does it.. But even if you are white-western-eruropean, the take-away from all of this is that your parents judgements on your partner should matter to you somewhat. Generally speaking if your parents are decent people, and they hate your boyfriend/girlfriend, they are right and you'll realise it sooner/later.