As you may have noticed, your LDS Account login name automatically becomes your publicly visible "screen name" when you come into the forum.
Since you probably weren't aware that when you chose your login, it's understandable that you may want to change it. That's easy to do by going to https://ldsaccount.lds.org.
Unfortunately, changing your name will break the connection to your forum account. When you come back in, it will be with a new account under your new name. Simply drop a PM to one of the forum Community Administrators, either mkmurray or myself RussellHltn and we'll combine your old account into your new one.
While you're checking out your profile, you might want to enter what country you are in for the location field. Otherwise, other forum members are likely to assume you are in the U.S. when they give advice.