16. A computer system comprising: at least one display device having a display area; and at least one processor programmed to: display the computer desktop on the at least one display device while the display area is unpartitioned; in response to receiving a first instruction to display closed captioning content, partition the display area into a first portion for the closed captioning content and a second portion for a computer desktop, the second portion being reduced in size with respect to the unpartitioned display area to make room in the display area for the first portion for the closed captioning content; capture closed captioning content from a user application executing on the computer system and/or an operating system of the computer system, wherein the closed captioning content comprises text and is selected from the group consisting of title information for a currently active window displayed on the computer desktop, information about controls in a window displayed on the computer desktop, text typed in a document, help information for a computer desktop or user application element, alert information provided by the user application and/or the operating system, and information redirected for output by a speech synthesizer; write at least some of the closed captioning content to a first buffer mapped to the first portion of the display area; write at least a portion of the computer desktop to a second buffer mapped to the second portion of the display area and not to the first portion of the display area; display the at least some of the closed captioning content from the first buffer on the first portion of the display area, wherein the at least some of the closed captioning content displayed on the first portion of the display area is selected to facilitate a user interaction with the user application and/or the computer desktop; analyze a context of the at least some of the text in the closed captioning content, wherein the context indicates an application type associated with the at least some of the text; replace the at least some of the text with at least one user-defined symbol based, at least in part, on the context before displaying the closed captioning content on the first portion of the display area, wherein a same word or phrase in the closed captioning content is replaced with different user-defined symbols in association with different application types; display the at least a portion of the computer desktop from the second buffer on the second portion of the display area; and provide an ability to scroll the at least a portion of the computer desktop within the second portion of the display area, without causing movement of the at least some of the closed captioning content in the first portion of the display area, and without causing movement of the first portion of the display area.
20. The computer system of claim 16 , wherein capturing closed captioning content comprises: intercepting one or more display calls from the user application to display content within the computer desktop; and including at least some of the intercepted content in the closed captioning content written to the first buffer mapped to the first portion of the display area.