Webform and Account

I have a webform questionnaire completed. I have correctly set the permissions on the node associated with the web form and set the permissions on the web form itself.
The questionnaire is for a medical practice. It can be completed by anyone on the staff. I don't want to set up separate users for each potential staff person and I don't want the staff people to be overwhelmed with setting up an account BUT I want them to be able to come back at another time and update their answers so I need a way to "manage" these users. There was a module for Drupal 6 called web form registration but does not have a D7 version. I have studied the Drupal material on setting up accounts and the web form materials on permissions but I am really turned around now.
What is the best way to manage this scenario?
Does every "authenticated user" have to complete an email confirmation of their account
Is there a way to provide a "universal" password and let a staff person log in using their email address each time they want to access their own questionnaire?
Is spambot the best module to eliminate robots from auto creating accounts or is Honeypot better?
Any advice is greatly appreciated!