By my ranking:
  1. MarginOfSafety
  2. QualityOfEarnings
  3. YouCanBeAStockMarketGenius
  4. FiveKeysToValueInvesting
  5. TheOnlyInvestmentGuideYoullEverNeed (AVOID)
  6. TheNewContrarianInvestmentStrategy (AVOID)

You should to get a grip on accounting before you read these. Perhaps it would be best if you read ConservativeInvestorsSleepBetter, Graham's Intelligent Investor, and The Money Masters to get excited about investing, and then went out and took a course (preferably two) in accounting.