Anyone who accepts Jesus Christ as the Son of God and Savior is a Christian. That is the dictionary defintion and we Mormons certainly qualify. We do not subscribe to some aspects of orthodox Christianity, but that just makes us unorthodox, not non-christian.
That is superficially true, but breaks down when we observe that the LDS notion of God's nature is different from the Christian notion of God's nature.
Specifically: the LDS notion that God the Father is a deified man flatly contradicts the Christian notion of God the Father.
That is the dictionary defintion and we Mormons certainly qualify.
The dictionary definition of "Christian" is actually considerably vaguer than the definition you've provided.
We do not subscribe to some aspects of orthodox Christianity
That is putting it mildly, but accurately.
but that just makes us unorthodox, not non-christian
The canonical definition of Christianity is a person who believes that God is a consubstantial, coeternal, immuted and immutable spiritual Trinity, the second Person of which entered into an hypostatic union with Jesus of Nazareth.
An LDS believer maintains that the Trinity is a mixed entity and that the persons of the Trinity are not coeternal, not consubstantial and not immuted.
It's a point of view, but it is not a point of view compatible with canonical Christianity.
Don't get me wrong - I find the modern LDS to be quite an admirable institution and I would never vote against any individual for being a member of the LDS. To the contrary, I would consider it a recommendation given the high level of integrity I've personally experienced in dealing with LDS believers.
But there is an objective standard of what constitutes Christian belief, and it is not found in the LDS.
It depends on what your definition of 'Accepting Jesus as...Savior' is.
That's where most non-LDS folks, including myself, get tripped up. Your definition of grace seems to be a bit...difficult. And in the eyes of most Protestants and Catholics, that's absolutely key to recieving salvation, the realization that it cannot be earned, and is not tied to anything we do beyond acceptance of our own inadequacy.
Feel free to explain how I'm wrong if you want. I'm not an ignoramous on the subject, I've read a few books and articles on Mormonism. The one that informed me the most was 'A Different Jesus?' by Robert L. Millit, who is a professor of ancient scripture at Brigham Young University. He convinced me that much of the anti-Mormon hysteria is untrue, he also convinced me that we have much, much more in common then not.
He failed to convince me, however, that the Mormon definition of grace wasn't ultimately substantially different from the concept that Protestands and Catholics give it, and I have a lot of difficulty with that one, because I believe it is key to accepting salvation.
That said, as I've said in this thread, I'd rather leave that up to God. I'm making no judgements myself, I'm just explaining the difficulty as I see it and what I think is the root cause of the conflict.