For the first one, yes.
There's a widget called "Directions" which you can just put on your "desktop" and it will have you configure it to set the destination and navigation type (car, public transportation, biking, or walking).
For the second one... Sounds like your MobileVOIP app would need a widget to support that. Or if it could hook into your device so that calls made were intercepted and the MobileVOIP app was made as the default app (I used GrooVeIP which did this). Then you could just use a Contact widget to call the contact and let the MobileVOIP app intercept/override it and go from there.