AR is like an overlay. Some examples: in Seattle all skyscrapers have an emerald overlay. So if you look with your normal eyes, you see a grey, aging building, but if you look with AR enabled, you see a nice, shining emerald monolith. As said, you can get more information about it by selecting the building. Another example is advertising. Most restaurants don't have physical boards outside with the specialties of the day, now it's an ARO (AR object, called arrow) that pops in your field of vision telling you about the chef's special.
VR is complete immersion. There you can compare it a bit with a Star Trek holodeck, but it's all in the character's head (as his body is limp at the time). How a node looks depends on what the designer of the node wants it to look like (meaning you as GM get to choose). Most Japanacorps go with a samoerai theme, where IC and analyse programs are Samoerai warriors, the browse program looks like a scribe helping you go through a library, and more of that. In VR you can do whatever you want.
With a reality filter, the hacker can override the sculpting of the node with his own (if he wins the test). That means he sees the node as he wants, but other users still see the original theme. For instance my hacker character uses a jungle theme (her persona is a black panther) where other animals and certain trees all have a meaning. Using the track program for instance for me is stalking a prey.