For the window size and position, use Settings -> Set As Default Lister and look at the Default Lister positioning options under Settings -> Preferences / Launching Opus / Default Lister.
For the folder format (view mode, columns, etc.), see the Folder Format FAQs, starting with Folder Formats: Quick Guide. It links to the other two FAQs at the top.
(I just finished re-writing that FAQ and the other two, by the way.)