What is the best way to express disagreement?

Well, you could say, “I don’t like it.” or even simpler, “No!” But, is this really a good way of conversation? I guess not. So, what other alternatives we would have? For example, you and you friends are talking about a TV show such as The Office. Well, your friends really like it but you think it is a dumb show. (I am not saying the show is really dumb. It is very fun to watch.) What would you say? If you are really close to your friends, it would be fine for you to say like, “Well, I do not like it. That show is stupid.” But, if you are not really close to them, I think you should use some other expressions like, “Well, I am not a big fan of it. I think the story is not really great.” Or, “I am not that into it. I think Mad Men is better.” (Mad Men is also a very great show. You should watch it too.)

I think people in America do use many expressions which are not direct. For example, if you just look up a dictionary to find out a verb to be used for disagreement, the word you can easily find would be “disagree.” Then, you can simply use it in conversations like, “I disagree.” or “I do not agree.” But, I am not sure it is really a good one to use, especially in business conversations. So, I would suggest to find and learn some of the expressions that can be used in situations where you need to say no or disagree.

In that sense, I think “I am not a big fan of it” is a good one. I have heard this expression a lot from my friends. My American friends! Do you have any other expressions you use a lot when you disagree with someone or you do not like something?