As is often the case, both sentences are completely grammatical and natural, but would be used in different circumstances.
Your "married" pair is quite complicated, because the context - and whether there are any temporal phrases - can change the meaning.
I have been married with no context, would be understood to mean "at some point in my past, perhaps more than once, I was married, but am no longer". But I have been married for three years means "I got married three years ago, and am still married". As always, the perfect implies some present relevance, but the meaning of that present relevance can vary: in the first case it is something like "looking over the span of my life up to the present".
I was married on the face of it says that at some point in the past I was married. It doesn't logically exclude the possibility that I am still married; but if I were, I would be unlikely to say "I was married". However, in answer to the question "What was your status three years ago?" I was married would be the expected answer, even if you are still married.
So, in the absence of any overriding context, the two statements I was married and I have been married refer to the same objective fact, but the speaker is relating to them a little differently.
Turning to your other pair of sentences: in 2, you are stating that you studied English in the past: you're presenting it as a completed event, with no particular relevance to the present. You're not denying a relevance (in fact, your second clause indicates that there is some relevance) but for the purposes of the discourse, you're not bringing out any such relevance.
In 1, you are choosing to present the event of having studied as having some present relevance. That present relevance might have several meanings. One might be an expectation that you still had some English; but your second clause refutes that. Another is that you are looking back over your life until now (as in the "I have been married" case). Another possibility is that your study was recent, and that is how I would understand the sentence.
If the study wasn't recent, I would expect 2.