I added a new email account to my BB curve, and now I have two icons on my home screen, one for my yahoo email, and one from my ISP. BUT, my messages folder also shows emails from those accounts as well as messages from facebook, twitter, etc. How can I stop the messages folder from showing emails? I only need one place to show emails, not two.

All mail goes to the messages folder. that is the way the BB works. Delete from one, it is deleted from all. You can always hide one so it doesn't show up.