... mi interessa...
Which is correct? La lingua Italiana mi interessa o Mi interessa la lingua italiana
The both of them are correct, but there is a small difference in the meaning.
If you say "La lingua italiana mi interessa", you are putting emphasis on the fact that you are interested in italian language (and not in another language or something else).
A: E così ti interessa il francese! (So, you're interested in French!)
B: No, no. La lingua italiana mi interessa! (No, I'm interested in Italian!)
A: Non hai interesse per nulla! (You don't have any kind of interest in anything!)
B: Non è vero. La lingua italiana mi interessa! (That's no true. I'm interested in Italian!)
If you say "Mi interessa la lingua italiana", you are putting emphasis on the fact that you have interest in something (that is the italian language, but it could be somethig else too). Actually, you are answering to the question: "what you are interested in?" or "what is your hobby?".
A: Che cosa ti interessa? (What are you interested in?)
B: Mi interessa la lingua italiana. (I'm interested in Italian).
Usually, the most used form is second one, but just for logical reasons: the first form is more used for contrasting or correcting something that has said before, few times you correct or contradict someone else when you are talking.
I hope I was clear. Sorry for mistakes in my english.
you only have to write lingua italiana with a small letter at the beginning. ;O)
I am scarcely in level 5 but what little i could see, the second phrase sounds better
How I have said the most common form is the second one "mi interessa l'italiano", because it follows the "normal" order of the phrase. But it would be wrong to say that the first form is incorrect. In fact, in some cases you can invert the normal order of the phrase to stress on a particular aspect. At a beginning level, this could be confusing, but I think you should know it, so as to make your own observations in the future.