Ajax submit comments

you might find these links handy if you’re going to code it yourself

http://byronyasgur.wordpress.com/2011/06/27/frontend-forward-facing-ajax-in-wordpress/
http://www.garyc40.com/2010/03/5-tips-for-using-ajax-in-wordpress/

I am fairly sure your URL is wrong url: “../wp-comments-post.php” – ajax in wordpress has to be sent (quite strangely) to/through admin-ajax.php (even if it’s not on the admin side). If you read the first link it is explained in a fair bit of detail. It’s a slightly odd a route to send the data on but that’s how it’s done it seems ( despite some new developments mentioned in the comments of both posts)