Turn off accessibility features after a specified time

On the General tab, under Automatic reset, select the Turn off accessibility features after idle for check box.
To adjust the number of minutes the computer can be idle before accessibility features are turned off, in the minutes box, click the arrow, and then click a number.

Notes

To open Accessibility Options, click Start, point to Settings, click Control Panel, and then double-click Accessibility Options.
If you enable this feature, all accessibility features except SerialKey devices will be turned off after the specified time.