Drupal crashes after webform install

Critical means that module is broken for every installation in the world, downgrading to Normal as my installations all work.

Have you upgraded Webform recently? Did you run update.php afterwards?

Recently i have found this new issue too, i uninstalled the module but the content type made by this module doesnt go.

That is behavior by design. You wouldn't want Webform just deleting potentially thousands of pieces of content would you? Webform merely just sets up a "Webform" content type by default, you can actually delete it if you so choose and then use Webform on other types of content.

Whenever I enable webform my site crashes down I don't understand whats the issue i have tried this module on different sites but the outcome is the same,my site goes blank.

I'd suggest enabling the "display_errors" option in php.ini on your server so that you actually get an error message instead of the "site going blank" (which I'm guessing means you're getting a PHP error of some kind). If you're capable of checking server logs, you should check those as an alternative to enabling display_errors. Without knowing what the PHP error is, there's not much information that we can provide to help solve the problem.

Closing after lack of activity.

Drupal 7.17
Webform 7.x-3.8

Every time I install webform it hoses my MySQL database. I get this error:

PDOException: SQLSTATE[HY000]: General error: 2006 MySQL server has gone away: SELECT filename FROM {registry} WHERE name

Unfortunately, I have recreated it several times. It is no fun to get out of. I have to manually remove the webform tables from the database. Repair and optimize the database and then run update.php.

I really need this module, but I do not know what to do.

PDOException: SQLSTATE[HY000]: General error: 2006 MySQL server has gone away: SELECT filename FROM {registry} WHERE name

Google for this particular error. It's not caused by Webform specifically, it's caused by your installation of Drupal exceeding the configured capabilities of your server. Installing Webform just pushed your installation over the top.