To remove speech recognition
Open Regional and Language Options in Control Panel.
On the Languages tab, under Text services and input languages, click Details.
Under Installed services, click Voice Recognition under the language you are using, and then click Remove.
To open Regional and Language Options, click Start, click Control Panel, click Date, Time, Language, and Regional Options, and then click Regional and Language Options.
Speech recognition requires computer memory and can affect your computer's performance, so you should remove it as a text service if you do not use it.
Removing speech recognition does not delete it from your computer, it only removes it as an available text service and prevents it from being loaded into memory. You can add it again at any time.
To remove the speech recognition engine from your hard disk, follow the instructions in the program with which it was installed, or use Add or Remove Programs in Control Panel.