Dad: Ahh, America: the land of the buffet. Isn't it amazing that we even have this dilemna. We have to think about what we think the local church should be for and be like, and then we can most likely find something pretty close, and then if we don't like it, we can try another one.
For a freshman in college, there is the new dynamic of being in a large group of peers and experiencing their energy and enthusiasm. That can make for an exciting and growing body of believers, and I wouldn't discourage you from enjoying that to the fullest. At some point you may want to ask some more long-term questions, which you are already doing (as usual): What is the local church? What is the purpose of getting together once a week? Is it important to be part of a congregation that will look more like what you will experience when you leave college?
As far as what you should do now, you may want to start with attending the student group to help you develop those positive Christian relationships with fellow students. That can be a tremendous strength as you go through your college years. There will come a time when those long-term questions become more pertinent. You may also experience the phenomenon of feeling like you've outgrown the college group. At some point it would be good to visit some local congregations and worship with a broader age group, and be part of a body with families living life in the real world. Nothing is a better teacher than living life with those who are actually living real life after college (other than living life after college yourself).
There isn't the perfect timing for everyone for doing this, so I suggest you just visit churches on occasion to remind yourself that someday you will end up being an adult with a life in a local congregation. Try out different things now while you can. Making mistakes and learning is all part of maturing in life, and these years are made for that kind of learning. There is much less to lose. Of course I'm not referring to moral mistakes. There is a lot at stake there, and that is one reason why having a solid peer group now is a good foundation for the other areas of learning.
One think you might try is inviting others to go with you when you visit a church and later talk about what it was like. Visiting churches can be an enlightening experience. If you decide to attend a local church, there may be a mid-week service for college students that you could still attend for the peer relationships.
Dad: The classic book on cults is Kingdom of the Cults by Walter Martin. It has an extensive overview of all the major cults. It's been so long since I've read it that I don't know how it's organized, but it gives an overview of each cult and then how they don't fit with Christianity, and how they are wrong. I doubt it's in a local library, but you may find stuff on line.
Read the overview in Wikipedia. It's a good summary of what I've heard before (you may already have). Then ask her what she believes, not necessarily what CS teaches. Politely dig deep, like if she believes in God, find out what she believes about God. If she believes that everything is good, ask her if there is evil or sin. Uncle Howard kept saying, "Everything exists in the mind of God. God is good, therefore everything is good." He had no answer for evil, except it was our inability to remove our minds from the imaginary physical world. I challenged him by pointing out that if we are wrong about the existence of the physical world -- which would not be a good thing -- how can something not good be in the mind of God if everything is in the mind of God and God is good. Anyway, you probably won't have to get too deep with her, because she probably doesn't really know what she believes, kind of like most Christians.
Your best bet is to stay in the Word, and just play dumb and ask a lot of questions that show that anything not in line with God's Word ultimately doesn't make sense. Also, if you pray for her and show true concern, you will be more likely to have the opportunity to share the Gospel. It is really amazing to me that I have never had to convince anyone that they were a sinner, or at least have sinned. What sometimes happens is that people think that God could never love them because they aren't good enough. I think you know how the Gospel answers that concern.
I will pray for you and your interactions. May God give you the relationship and words so that you can be part seeing the birth of a new creation in Christ. Don't be discouraged if it doesn't happen fast, or you ever see it happen at all. You may be #6 out of 16 that she hears from to get her to the point of giving her life to Christ.