I would be careful with free lunging him first, but I would definitely establish control on the ground before riding him.
Get a well fitted halter and lead. Teach him to back, move forward, sideways, etc. This can establish respect as well. Free lunging I worry about because you say you are a novice rider. A lot of times novice riders paired with novice horses just end up on being a big chase. Also, depending on the horse, I have seen horses get sort of aggressive when free lunging and they will attempt to come into the middle, pin their ears, kick, etc. It's just them attempting to dominate you (which it sounds like he is the dominate one here), but it can be intimidating to an inexperienced rider.
Do you have any friends who are a bit more comfortable with horses? You don't need a professional trainer (Even though it would be ideal) but a more experienced rider may be beneficial.
Also, books, DVDs, movies, etc. That way you can SEE things happen and know better if you are getting the right response.