[eluser]Jamie Rumbelow[/eluser]
Ryan,
Helpers should only be used for small bits of repeated code or functionality that you use explicitly in your views. Any data related queries whatsoever should go in your models, and the login functionality itself should either go in a controller (if it's only being used once), or in a Library (if you're calling the same function more than once).
The MVC pattern might be a bit weird when you start out but it really makes sense when you've been using it for a while; and you'll be glad it's there!
Jamie