Here are a few good articles which address in depth various aspects of the current economic crisis. They are a bit long, but worth the time to expand your understanding.
Anatomy of a Train Wreck by Stan Liebowitz
Rather than sub-prime or prime status, Liebowitz shows that the more relevant factor in default rate for mortgages is adjustable vs. fixed interest rates.
Triple-A Failure by Roger Lowenstein
This article looks at the role the rating agencies played, including the potential for conflicts of interest, the existence adverse incentives and errors caused by the rating process itself. One aspect of the role of rating agencies this article does not stress is the lack of free market competition in the field of rating agencies. Regulatory control and certification by the S.E.C (through requiring and conferring "Nationally Recognized Statistical Rating Organization" status) leads to the destruction of competition for quality that all such government standard-setting causes.
An AP Stats Lecture by Arnold Kling
Here Kling uses the dilemma of needing to balance Type I and Type II statistical error as one of the factors leading to lending to borrowers with credit credit risk. This provides a more benign analysis of the alternatives faced in the mortgage loan process, rather than looking to vilify predatory lenders or deadbeat borrowers.
The Credit Crisis and Moral Hazards by Eugene Halloway
This article focuses on the moral hazards which occur when government interferes with the free market. While intending to provide protection and security, the actual effect of government regulation is something quite different.
The Greenspan Fed in Perspective by Roger Garrison
Includes some history of the Fed as well as explanations of and reasons for the shifts in post-1970's Fed monetary policy.
And for a novel idea on a possible solution to the problem: Let's try freedom!
The High Cost of Washington's Price Manipulation Policy by Yaron Brook and Don Watkins