The Voting plugin is designed as a sort of "support community" plugin. It converts your forum into something similar to stackoverflow.com, and part of that is renaming the button. You can easily reverse this change by doing the following:
Create locale.php in your conf/ folder. Paste the following: <?php if (!defined('APPLICATION')) exit();
$Definition['Start a New Discussion'] = 'Start a Discussion';
The culprit is the definitions in the file plugins/Voting/locale/en-CA.php file these can be overridden by definitions similar to that given by tim above, as always there are many ways to do things, the file in the voting plugin overrides the out of the box behaviour. Another way is to delete the file, better to modify the file or even write your own locale definitions making sure your definitions take precedence.
Comments
Create locale.php in your conf/ folder.
Paste the following:
<?php if (!defined('APPLICATION')) exit(); $Definition['Start a New Discussion'] = 'Start a Discussion';Vanilla Forums COO [GitHub, Twitter, About.me]
these can be overridden by definitions similar to that given by tim above, as always there are many ways to do things, the file in the voting plugin overrides the out of the box behaviour.
Another way is to delete the file, better to modify the file or even write your own locale definitions making sure your definitions take precedence.