Under consideration are the general set of Human computer Interaction (HCI) and Educational principles from prominent authors in the field and the construction of a system for evaluating Virtual Learning Environments (VLEs) with respect to the application of these HCI and Educational Principles. A frequency analysis of principles is used to obtain the most significant set. Metrics are devised to provide objective measures of these principles and a consistent testing regime is introduced. These principles are used to analyse the University VLE Blackboard. An open source VLE is also constructed with similar content to Blackboard courses so that a systematic comparison can be made. HCI and Educational metrics are determined for each VLE.