My advice? Don't expect them to immeidately adapt to your style, even if they are not new to roleplaying games. The best thing is to (1) start taking notes as to what in the game lights them up - what do they get enthused about? Not every one will be necessarily "just combat," so listen carefully. Secondly, find what drives them, and attach roleplaying behavior to that, sparingly at first, but increasing slightly session by session.
(A) finding what they enjoy about a session and playing to that ensures they keep enjoying and coming back.
(B) introducing sparing roleplay elements increasingly gets them used to the idea. Some people are not comfortable with being in-character, and some aren't comfortable thinking "what would the character do." However, you can get them more comfortable as time goes one.
(C) beware "casual players" - these are the guys who just like to show up and contribute, but can't stand the spotlight. Their focus IS the gathering, not the game per se, and pushing them too far to the spotlight can turn them off. Accept them for the blessing that they are - anchors who will ALWAYS show up for a game or movie night.
What does it mean? It means starting a small conversation in-character, but only for a minute or so, for a very specific purpose - info gathering, or talking out of hostilities (or even getting INTO hostilities). Directly address a character, and they'll usually respond in kind. Aim for only two or three of these incidences per session, gradually increasing as sessions go on.
You can't expect a new group's style to immediately gel, and it sometimes takes a few months to really get to know one another, how to act and react, etc.
Robin's Laws to good gamemastering and the DMG2 are two of the best books on the subject of helping a group "gel together" that I know of.