Distance: 8 blocks and teach class
Okay, here's how I see it:
1.Yes, House helped/killed the guy with Lou Gehrig's die before the pain was excruciating (for the same reason he promised to kill/help Thirteen, which is why she had the line reminding us of House's promise).
2.No, the script wasn't perfect and in fact was disjointed which I think is just in keeping with House as a person so that is better than some smooth, perfect package.
3. The most important and brilliant line was the last one: House saying "Cancer is boring." Because House Loves puzzles and Hates boredom and is bored after he has solved a medical puzzle, House has a Solution for Wilson's cancer! At the very least House is going to prolong Wilson's life, and they are going to have a long, meaningful life together - possibly as a medical duo sleuthing and curing other people's illnesses. Wilson can start at another hospital because he still has his medical license, and House will be his silent partner, the brains behind the operation.
Or something; the main thing is House is alive, and while he is anything is possible in the puzzle game of life.