1. You get to "heaven" by grace not by good works.
Depending upon your denomination I believe you can get to heaven by good works as well. Interestingly some say that having grace or being filled with the holy spirit will lead you to do good works anyway, something I rarely see confirmed by observation but I digress.
Most Christians agree that you need *both*. Some Christians side more with grace, but clearly express that good works are the necessary result or corrollary of grace. Catholics do *not* believe that good works can get you into heaven, as this implies that *we* are the arbiter and source of our salvation. Catholics do place a premium on good works as corporal acts of mercy, and we do believe that they can be "assigned" to specific things like souls suffering in purgatory, and we do belivee that God will recognize our good deeds (the bad deeds too).
In that "heaven" is a gift from God, the answer is clearly *grace*. Good works, being tangible, are more readily apparent and of course Christ commands us to do good works. Many Christians are not even all that interested in creating a dichotomy, and think this all goes together.
2. Grace is basically believing in the one true god (or all 3 of them if you are a trinitarian) and that Jesus (Joshua) died for your sins.
No!
Grace doesn't come from ourselves! Grace, or graces, are gifts from God.
3. The only unforgiveable sin is not believing or having faith (not having the holy spirit) meaning you don't have grace. If you don't have grace then you don't get through the gates.
There is no general Christian articulation in response to this.
I believe that *every human* will face God. I think most Christians believe that. Some humans will decide that God is anti-God, or Satan (i.e. blaspheme against the Holy Spirit). This would be the unforgiveable sin, saying God is the opposite (in nature) to what he actualy is. I think this is a common Christian understanding, though others might not articulate it as I have.
4. Hell isn't actually a place, it is being apart from god.
Right. Although some Christians do believe it is a physical location, in the center of the earth to be specific. Even Robertsons and Falwells describe Hell as a state of being more than a physical place.
5. If you attain grace then you are actually forgiven for not having attained grace before so the unforgiveable sin is actually forgivable as long as you repent and believe.
We don't "earn" grace. We accept it. It is offered to all, not just the best of us. Christians focus (some say too much) on the fact that we do *not* deserve God's grace, or, that God offers it to us despite our sinful nature.
The unforgiveable sin, in my opinion, is not contingent on ignorance.
If anyone has anything to add to that I'd welcome additions or corrections.
It's a tough one, to come up with a total and rigorous statement of general Christian belief. In my experience, Christians can and do partially agree with a variety of explanations for the same dogmas, while favoring a particular way of explaining it. To us, theological explanation is not as important as the the faith in the specific belief. We explain it as best we can, knowing full well that the reality is the important thing.
-Elliot