I am using jQuery with the validate plugin at http://docs.jquery.com/Plugins/Validation/validate
I want to prevent the form from submitting after its validation and
You can code this in a very simple way via "jQuery Walidate". http://jquery.dop-trois.org/walidate/
There you can code a function, that will be executed on submit. Look for Callback in the Documentation.
Maybe you can validate externally without using a submit button:
if($("#myform").valid()){
alert("Do some stuff...");
}