When i create new user through salesforce UI i dont want the password notification to be sent to the User .Is this possible ?I know one solution is to uncheck the generate Email Notification and new password email check box .Is it possible through trigger before insert in case the admin forgets to uncheck that ?
You have two options.
While creating the new user, dont put the correct email address. You can either use a dummy email address or maybe the admin's email address. This way emails will not go to the actual users. However there is downside to it. The downside is that you eventually have to change the the dummy address to the correct email address. And when you do that Salesforce send an email to the user asking him to confirm the change. If your users dont mind receiving this email, VOILA.
Create a VF page that should look just like the new user page without the checkbox. And then the code behind insert a new user object using the data obtained from the VF page.
Also please let me know if any of these two solutions work. So that others may also benefit from it.