i got a form and i want to show it as window dialog and able to submit it via dialog how i do that? what module i need?
also, how can i make that i get unique class for each form element?
The Popups module is awesome for this.
You can easily target a page (with your form), and it puts the content of the page in the popup. It opens it similarly to a lightbox, but it does not open a new browser window.
Drupal has a module for modals.
As for the unique class names in your form, this article may be helpful.