I'd actually like exactly the opposite behavior (I just filed a new feature request about it): I'd like the app to remember what screen I'm on and always bring me back to that screen when I launch it, even if it was previously unloaded. Both the Toodledo iPhone app and the Toodledo Web site can be configured this way, and it's exactly the behavior I'd want. So while I agree that it would be useful to allow the app to be configured to always return to the home screen if that's what the user wants, it should _also_ be possible to configure the app so that it always returns to whatever screen you were last on.

Using the default widgets isn't really the solution because they take way too much space on the screen.
Having a 1x1 widget could be a decent workaround, but it's doesn't allow the same flexibility : for example you cannot start in the "folders" view with a widget.

Plus, having the startup screen reset everytime the app is brought to front would definitely be a nice addition if the "Ability to add custom views to home page" is implemented :
http://utl.uservoice.com/forums/149475-new-feature-suggestions-and-bug-reports/suggestions/2588358-ability-to-add-custom-views-to-home-page?tracking_code=48cfbe344bfcc27ca41d2e0b890ab2f5

I enter Ultimate To-Do from a widget, so always get the widget view when I click on it, which is customised to the view I want.

See also the suggestion for a 1x1 widget elsewhere (with number of tasks on it) which you can click on to open the view.