You can only customize views in SPD for 2010. In 2007, the only thing you can do with SPD is create custom data views, but those aren't list/library views.
I suggest creating NEW views that show the same fields as the old views that are wierd, and then try to delete the old views and use the new ones that have the Type field instead of Edit. Honestly, based on what you've described, I'm thinking that it's not the Edit button causing this issue, but rather the nature of these strange views that is causing it. I've never heard of what you're describing, so I have no idea how it happened. Views don't have permissions, so it's not like you are being restricted from their settings. They must be customized or created in some way I've never heard of.