I don't think it can be as simple as you'd like.
The only ways to get FM Go onto the iPad is from the App Store app on the iPad or through iTunes. And you can't prevent the sample databases from loading (though you can delete them).
You can e-mail your database which is a simple way for users to open it.
Is it possible to write a script to remove those files when they launch your app. But they will still see those files the very first time.