ZoomText Magnifier/ScreenReader allows for typed text to be echoed with NeoSpeech voices as well as having text read by the point of the mouse and automatic document reading with various verbosity settings. The AppReader will provide text to speech within other applications such as Adobe Acrobat. Desktop and web finder are separate facilities that help with searching and working with files and links.   

This picture was taken from the University of Southampton Assitive Technology Serivce web pages offering guidance on using the software and the University of Cardiff also have a Zoomtext guide page

 The RNIB have a technicall sheet on using computers with low vision.