The Law, contained within the Pentateuch, is the character of God. It reveals truth about His holy and righteous nature, and rightly names sin for what it is - that is, a violation of the character of God. It contains the Ten Commandments, but also a lot of other various things for every day life.
Paul, in Romans, explains the Law as contrasting our filthy, sinful condition with the perfect character of God. That being said, Paul continues on to show that through Christ, we are dead to sin and the Law (making Jesus the best loophole ever!).
So are we to disregard the Law and break all the commands just because we are no longer cursed under it? By no means! Jesus says that the greatest commandment is love God with everything you have (Matthew 22). The true Christian will naturally uphold the Law (even though he doesn't have to perform it for salvation) because he loves God more than anything and the Law is God's true character.
Hope that helps