Regarding the context-menu crash, try my advice in this FAQ:
Basically, it is probably a conflict between a 3rd party program and Opus. You can turn off 3rd party items on context menus and (also then enable only specific ones) but the best thing to do is work out which one is causing the problem and let GPSoft know so they can work around the problem. (It's often things assuming that only Explorer will ever show their item, and take advantage of that in dubious ways.)
Regarding the Folder Options, I suspect you're being confused by the content-type detection system which is on by default in Opus 8. This will detect, for example, that a directory has lots of image, music or movie files and change the format. You can either turn this off or edit/add/delete content groups and their formats.
To turn it off use Preferences / Folders / Options: Enable Folder Content Type detection.
To edit the formats go to Preferences / Folders / Folder Formats
To define/edit/remove content groups go to the opus Filetypes editor, via the tray icon.