Hi Nathaniel,
That is a tough place to be! I sadly concur with your assessment of the L.D.S. Church, and have had reaching it to Mormons on my heart for quiet a while.
One of the best resources I would recommend is the book, "One Nation Under Gods: A History of the Mormon Church" by Richard Abanes. It's a hefty copy, but if your in college you may appreciate that size of book.

I recommend it because of a table it has that is simply a rundown of the differences between Mormonism and Christianity. Even more helpful is the meaty reference index at the back to support the table it provides. (I don't know if I would just show her the book though. She will probably feel uncomfortable with it as a whole, but maybe just photo copy the table?)
It may help create some more thoughtful conversations on the differences with a clearer outline.
I'd also recommend you get a copy of their four scriptures. They have a bound version of all four books they call "The Standard Works" I find that it's common for Mormons to not be fully aware of their teachings so I keep one myself and put color coated tabs in it to show clear context right from their own text compared to the bible they have.
I think it's wise that your seeking help on this topic. I don't know you, so I feel the need to say the (possibly obvious) necessary warning that you're on the right track to be concerned. If you marry someone that isn't equally yoked even if she is a wonderful girl, (and it sounds like she really is!) that things will not go well. Two become one, and that's huge!
Okay. I really think you didn't need that, seeing your question, and how you worded yourself but I didn't feel right not putting it there.
I do think it's more then possible you could lead her to Christ! And that's more then enough reason to wait on this in my opinion, but may I make a few suggestions on that?
One, I would put a hold on your relationship. Let her know your not looking elsewhere, and still get together the same amount, but don't move forward until you have this figured out. I would let her know this is for her sake too, because you would not accept being Mormon, (temple marriage and so on-) so this is for both of you.
If you are being "physical" together, I would work on stopping that for the time being. I'm not even talking about sex (as that should come after marriage and seeing that you said she was moral I assume it's not an issue) but kissing or hand holding "couple" things. I would do that simply so your head is straight through this time. Maybe even have a friend be there with you both through this if that's a problem? (Not knowing you makes these a answers awkward, sorry about that.)
Two, I'd set some goals, and see what you both think you would need to figure out between you of you were to marry. (Seeing that marriage is the end result of dating, that seems reasonable to me, even if that's not the plan yet.)
Three, I'd do some open ended searching with her. I bet your already studding quite a bit, but turn this into another class for both of your benefit. (I would always pray before you start and maybe have a quick devotional together before each chat) and take turns telling what you both believe, and then seek out more on that. (Possibly using the One Nations Under God's table as a guideline?)
And lastly, I'd consider this- even if she gives her life to The Lord, your going to possibly want to wait on the relationship for a while. She would be a new Christian, and you STILL might not be equally yoked. Knowing if she's saved or just moved by your heart and not The Lord would take time.
Also, it would be hard to marry someone that is far more knowledgeable in faith then you are, and that's where she would be at first. It would be more like a parent child relationship for a while between you two and that's not fun when your adding on the stress of new marriage. You would want to stand by her and let her become a new creation in Christ and support her thought it over time.
I'm sure she's worth it if it came to that, but I'm betting it will be super hard to slow down and wait on your relationship when she came to Christ. All that new hope and beauty in her heart, and the joy of having supported her and been there all along and then you have to keep your relationship at a distance!? Bummer!! But that's what I would recommend. For a while. Maybe involve your pastor in the time you should wait?
But I'm just some person on the internet, so take what I say with a grain of salt.
I'll be praying for your both tonight. I hope that no matter how this story turns out, that you'll see the Hand of God in your life for this time and that you'll only grow closer to Him. (Oh, and I hope you end up with someone perfect for you- this wonderful young lady or someone else God will bring I to your life. What ever it is may you be blessed, my friend)
Alright- I'll go pray now.
