I have to go with Blood Diamond on this one, that movie was simply amazing, great acting and I really like movies that are based on a true story and this one is one of my favorites. The ending was really good, it really surprised me as well, didn't expect that to happen.
The Last King of Scotland was good too, but it was too short for me. But Forest Whitaker still played a very convincing Idi Amin.
Blood Diamond gave me a lot better insight on what happened in those actual events, and it's sad about what they did to the kids. Now everytime I listen to Kanye West's song, "Diamonds from Sierra Leone" I can actually pick apart every line.