What are some of the key elements of a screen reader that can be used to help someone learn to read fluently?

There are two general types of screen readers; those for people with visual impairments and those for people with vision.

Key Elements for a Screen Reader for Visual Impairments:

• Use application without a mouse
• Ability to control voice and speech rate
• Ability to change voices; gender and pitch
• Use of improved natural voices
• Ability to convert an image to text in order to read it with a screen reader (OCR)

Key Elements for a Screen Reader for someone with vision:

• Ability to convert an image to text in order to read it with a screen reader (OCR)
• Ability to control voice and speech rate
• Ability to change voices; gender and pitch
• Use of improved natural voices
• Ability to select word and sentence tracking, or no tracking
• Control of font size and colors, background colors, and tracking colors
• Easy stop and start of speech and placement of curser

Can you suggest some affordable screen readers that you think would have the key elements that you are talking about?

Screen Readers for a user with visual impairments:

We have not completed a thorough product evaluation of these screen readers. The products that we have used and know will work are Jaws, WindowEyes, Kurzweil 1000, and Open Book. There are more affordable screen readers available that more than likely will work well to learn to read; we just haven't used them yet. Some of these are Thunder and System Access. Following is a web page describing these and more screen readers:
http://www.disabled-world.com/assistivedevices/computer/screen-readers.php

Screen Readers for someone with vision:

There are many screen readers that will work very well. Some are quite expensive, providing many additional features that sometimes will confuse a new reader and new users of computers. We recommend starting with as basic an application as possible to learn to read. These products are very affordable. The user can upgrade to another application after they gain confidence and reading skills. The entry level applications are ReadPlease Plus, Premiere E-text Reader, and Text Aloud. There are others that will work fine. The applications mentioned are only the ones we have used. More advanced applications that we have used are Kurzweil 3000 and Premiere Talking Word Processor. The added features can be very beneficial in helping with learning skills after the basic reading skills are developed.