Google now should work for one of these items. I believe you can say "Navigate to Archie Bunker's address" and it will open the navigation window. From there you will probably have to touch the begin navigation button, so not totally hands free. Also if you have Google now open you can say "Hello Google" to activate the voice search/navigation feature hands free. You will want to go into your Google now settings and make sure you have Navigation, and Contacts selected as searchable.
As for the calendar issue, if it's a place that you can Google you should be able to navigate there, but your request will have nothing to do with your calendar event. So you can't say "Navigate to Bart Simpson's birthday party" or "Navigate to my 3:30 appointment on the 6th." Although you might try the latter. If you have the address entered in away that Google Maps recognizes with no extra information in that field, it might work.? Obviously saying "Navigate to 6925 Hollywood Blvd, Hollywood, CA 90028" will work, and again you probably have to press begin navigation.
One last note you will want to have GPS enabled or it will ask you to enable it before it can navigate.
Hope this helps. I'm going to try it out after work, just to see for myself.