Public Events with Groups

I have a Drupal 5.3 site running Organic Groups, Orgranic Groups Calendar and Events modules, among others. I would like to find a way to show "public" events to all site visitors in the Events block, but hide events that are for specific group(s) only (i.e., not marked as public). Can the Events module filter by this criterion, or should I forget about the Events module altogether and use a custom content type and Views for events?

Thanks for any input on this.

HAJ