Well, Michelle, it's really simple to use a messageboard.
There are different sections of this messageboard to discuss certain aspects regarding Titanic. For example, if you have a question about one of the passengers, then you can post your question in the "Passenger Research" forum. If you want to bring up something regarding the movie, then you go to "Titanic Movies".
Most messageboards can turn into a chat environment, but this board tends to work in two ways. At first, everyone stays on the topic. But then, either the question gets answered, and no more posting occurs in that thread, or the thread continues, but with people discussing things that aren't related to the original topic!
It's a strange group around here, but most of them are rational!
The best advice I can offer is to take some time and just look through every forum on the boards that sparks your curiosity. And, under the "Miscellaneous" section, there is a forum called "Introduce Yourself". Why not post some info about yourself, and in particular, where did you first hear about the Titanic?
I hope some of this rambling was helpful.