It kind of depends on if you like revenge-oriented crime / thrillers. I know that I do

The basic plot is that Clyde Shelton (Gerard Butler) witnesses the brutal murder of his wife and child in the foyer of his own house. The perpetrators are caught but a lazy judicial system allows one of the two men to serve only a suspended sentence and is released from prison after only a few years. Feeling as though the system is incapable of serving justice, Shelton takes matters into his own hands in a rather diabolical fashion. It is the first time I can recall anyone ever using puffer-fish poison in a film.
When he captures the man responsible for his family's murder, he is ever so slightly brutal towards him. As a matter of fact this is considered one of the most brutal scenes ever depicted in a film and I am just going to leave it at that.
Jamie Foxx's role in all of this is that the is the Prosecuting Attorney during the trial that results in Clyde's anger and subsequent revenge. He finds himself being one of the subjects of Clyde's far-reaching and meticulously planned vengeance later on.
While the premise isn't exactly unique, the acting is decent and the pace of the film is just right for a nearly 2-hour film. You stay interested in what is going on and the movie isn't terribly predictable either (which is always nice.) At least for me, i found myself torn between whether or not I should be rooting for the bad guy despite the fact that he does horrible things.
I said in the title that this movie is better than average and that is exactly how I feel about it. The only reason that I can say that it isn't great is that the whole concept of one person being capable of what Clyde is capable of in this movie is incredibly unrealistic and kind of borders on absurd. However, it is fiction and if you can accept that you will find this movie entertaining.