@snow

These are good questions.

1st story: Two things to notice from this:
1) Saul's motives for doing this are wrong (to kill David), and you'd be hard pressed to find Christians who defend Saul's actions, especially this one.
2) It must be remembered that the Philestines and Israelites were mortal enemies and IIRC actually at war at the time, so killing Philestines isn't entirely unreasonable.

2nd story: This is an interesting point. David did pay the dowry tho...