I guess you need to weigh a couple of things, and then decide how you want to do it.
First and foremost, you should decide if you actually want to come out to this person. Based on the fact that you're going to go to college, I assume you're young. Odds are that you and your girlfriend will not be a long term item. If you think there's a chance that this may be true, and you feel your safety is at risk, you might want to wait and see how the relationship proceeds before coming out to her father. If you think she can keep the secret, discuss it with her, and see how she thinks her father will react. If things don't work out with her, then you don't have to deal with a potentially dangerous situation.
If you do need to tell him, because you think the relationship will stand the test of time and he needs to know before you leave, then do so safely by taking some precautions. First, do it in a public place. He's much less likely to start something violent if you're at a Chili's or a mall. Second, have someone there who can help and protect you. Preferably your parents, if they're the type who will support you. Third, as with all coming outs, hope for the best and plan for the worst. You may need to keep in mind his reaction and what that may mean for you and your girlfriend.
Honestly, based only on what you've said in this thread, it doesn't seem like he'll physically attack you. Those condemnations, while bigoted, are not the stuff of murder. It sounds like he just doesn't like the idea of LGBT people in the abstract, and has never been faced with them in reality. My dad was the same way, and he came around.
Good luck in whichever course you take, and I do hope you and your girlfriend buck the odds.
