Just ask yourself : scrollTop is a property that indicate the distance from the top of the document, in pixels.
There, you ask jQuery to animate the scrollTop to "#fields2", which is a string.
So, first, I guess you try to retrieve the distance of element #fields2 from top ?
This way : $('#fields2').offset().top
jQuery('.scroll, .send_btn').click(function (e)
{
e.preventDefault();
var dest = $('#fields2').offset().top;
jQuery("html, body").animate({ scrollTop: dest }, 'slow');
// If you need to submit a form, with an input like : <input type="submit" class="send_btn" value="Submit"/>
if(jQuery(this).hasClass('send_btn')) { // check if you've clicked on .send_btn
$(this).parents('#myForm').submit(); // submit the form.
}
});
Note : I replaced return false by e.preventDefault(). return false is not standard way to stop fire events.
Edit :
As e.preventDefault(); stops the events on the element, you must manually submit the form with jQuery, as seen in the code above.
scrollTop: $('#fields2').offset().top