It would be hard to find anyone in the bible that God liked more than David.
For a concise summary of the killings of David,
He was directly selected by God to be king, and "the Spirit of the Lord came upon David from that day forward."
And the LORD said, Arise, anoint him: for this is he. Then Samuel took the horn of oil, and anointed him in the midst of his brethren: and the Spirit of the LORD came upon David from that day forward. 1 Sam.16:10-13
His heart "was perfect with the Lord" and "the Lord God of hosts was with him."
David ... grew great, and the LORD God of hosts was with him. 2 Sam.5:10
His [Solomon's] heart was not perfect with the LORD his God, as was the heart of David his father. 1 Kg.11:4, 15:3
He walked in God's ways and kept his statutes.
And if thou wilt walk in my ways, to keep my statutes and my commandments, as thy father David did walk, then I will lengthen thy days. 1 Kg.3:14
And (with the exception of the matter of Uriah the Hitite) he did what was right in the eyes of the Lord in his every act throughout his lifetime.
His (Solomon) heart was not perfect with the LORD his God, as was the heart of David his father ... Solomon did evil in the sight of the LORD, and went not fully after the LORD, as did David his father."
David was one of the most disgusting characters in all fiction, yet "his heart was perfect with the Lord." 11:4, 6
Because David did that which was right in the eyes of the LORD, and turned not aside from any thing that he commanded him all the days of his life, save only in the matter of Uriah the Hittite. 1 Kg.15:5
He was, according to Acts, a man after God's own heart.
And when he had removed him, he raised up unto them David to be their king; to whom also he gave testimony, and said, I have found David the [son] of Jesse, a man after mine own heart, which shall fulfil all my will. Acts 13:22 (See also 1 Sam.13:14)
So if we want to know what type of person God likes, we need only look at David. Those who believe in the bible should try hard to imitate David, to always ask themselves "What would David Do?" in any particular situation.
With that in mind, then, let's look at some of David's godly acts.
He kills Goliath with his sling, beheads him, and carries the head back to Jerusalem. 1 Sam.17:51-57
He and Saul have a contest to see who can kill the most people for God, and the women act as cheerleaders saying, "Saul has killed his thousands, and David his tens of thousands." 1 Sam.18:6-7
He kills 200 Philistines and brings their foreskins to Saul to buy his first wife (Saul's daughter Michal). 1 Sam.18:25-27
He acts like he's crazy, scribbles on the gates of Gath, and lets spit run down his beard. All this he did in front of Israel's enemies in the hopes that they would take him in and protect him from Saul. 1 Sam.21:12
He "inquired of the Lord, saying, Shall I go and smite these Philistines? And the Lord said unto David, Go, and smite the Philistines ... So David smote them with a great slaughter." 1 Sam.23:2-5
He vows to kill "any that pisseth against the wall." 1 Sam.25:22, 34
He "smote the land and left neither man nor woman alive." 1 Sam.27:8-11
He had many (like Joseph Smith, no one knows how many) wives. 1 Sam.30:5
He tells one of his "young men" to kill the Amalekite messenger who claimed to have mercifully killed Saul at Saul's own request. 2 Sam.1:15
When Joab (David's captain) kills Abner, David says that he and his kingdom are not responsible. The blame, he says, lays with Joab. So David curses Joab, his family, and their descendants forever. Let them all be plagued with venereal diseases and leprosy, starve to death, commit suicide, or lean on staves. 2 Sam.3:27-29
Some of David's men kill Saul's son and bring his head to David, thinking that he'll be pleased. But he wasn't. David has the assassins killed, their hands and feet chopped off, and their bodies hung up (for decorations?) over the pool in Hebron. 2 Sam.4:6-7
He says that whoever kills the lame and the blind will be his "chief and captain." 2 Sam.5:8
He asks God if he should kill some more Philistines. God says yes, and he'll even help. So David and God "smote the Philistines" again. 2 Sam.5:19, 25
He dances nearly naked in front of God and everybody. Michal criticizes him for it and Godpunishes her by having "no child unto the day of her death." 2 Sam.6:14, 20-22
He kills two thirds of the Moabites and makes the rest slaves. He also cripples the captured horses. 2 Sam.8:2-4
He kills and tortures thousands of people, "and the Lord preserved David withersoever he went." 2 Sam.8:6, 14
He sees a woman (Bathsheba) bathing and likes what he sees. so he sends for her and commits adultery with her "for she was purified from her uncleanness." She conceives and bears a son (which God later kills to punish David). 2 Sam.11:2-5
He tells Joab (his captain) to send Bathseba's husband (Uriah) to "the forefront of the hottest battle ... that he may be smitten and die." In this way, David gets another wife. 2 Sam.11:15, 17, 27 (This is the only thing he ever did wrong. Everything else was "right in the eyes of the Lord.")
He tortured or enslaved (depending on translation) the inhabitants of several cities. 2 Sam.12:31, 1 Chr.20:1-3
He shows unusual restraint and "went not in unto his concubines." Instead, he imprisons them as a punishment for being raped by David's son, Absalom. 2 Sam.20:3
To appease God and end the famine that was caused by his predecessor (Saul), David agrees to have seven of Saul's sons killed and hung up "unto the Lord." 2 Sam.21:6-9
Old King David tries to get some heat by having a beautiful virgin minister unto him. 1 Kg.1:1-4
In David's last words, he commands his son Solomon to murder Joab. 1 Kg.2:5-9
So if you believe and trust in the Bible, you should try to follow the example of David in everything you do. Just ask yourself in any situation, "What would David do?", and then do likewise. That way you can be sure to do (just like David did) "that which is right in the eyes of the Lord."