Note that below opinions are of a non-native English speaker.
I am one of those few guys who mainly aim to learn how to write, not to speak, in English. So simply I pay most attention to writing skills, to which I include not only grammar but also style and general writing skills. I pay almost no attention to conversation and dialogs, but when it comes to using the language in real life, I have no real problems with it, though I'm much worse in speaking than in writing. When I write I have time to think and to construct sentences and to revise and, last but not least, I have dictionaries and reference books, reading of which, by the way, do not make me sleepy whatsoever. In fact, I love reading reference books on English and on writing, have read quite a few of them, and am planning to read more of them. It's a kind of hobby of mine, and you are free to think anything about me in this regard; you may even think I am a freak - in fact, I think it myself.
Concluding, what you aim at should help you choose how to learn English. However, I believe at the very beginning stage of learning English both grammar and conversation are equally important. Later you will be able to choose what you really want to achieve and do with your knowledge of the language.
Nyggus
