Someone asked what I meant by saying the choice between good and good is a Christian ideal. I just pulled it from my hat of smart-sounding sayings from Catholic saints, but I can discuss it further.
1. The Christian belief is that true freedom is choosing God, who is the ultimate good. When we choose to sin, we turn away from God and become enslaved by the body and our senses. That is, sin harms our capacity for freedom; you can easily see this in extreme cases of alcoholism and drug abuse.
To have true freedom, we must avoid sin and choose God. To paraphrase Jesus, he is the Truth that sets us free. This means true freedom is a choice between good and good. It is not a choice between good and evil; evil is not one of the options of true freedom, because it limits freedom.
2. Saint Augustine is the Catholic theologian who worked out the theory that evil is not a positive force. Rather, evil is the absence of good. It is a distinct lack of goodness,
a) X's goodness has diminished/lessened/corrupted
b) X is evil
Evil does not have positive existence; instead, like a leech, it depends on goodness for its existence. In every bit of evil, there is at least some goodness somewhere; otherwise, the evil could not possibly exist. From this, it is argued that every choice is a choice between good and good; you should choose the option that has more good than the other.
3. It's more proper to categorize the idea of "good versus good" as a Western idea than an Eastern one. Traditionally, the Eastern world sees the world as a battle between good and evil, like yin versus yang or Darth Vader versus Luke Skywalker. The Western World officially rejected this idea with Manicheeism, but it's still been very popular with Westerners before and after that.