This year according to the map at inauguration.dc.gov/ (see below) the vehicle restrictions appear to be limited to our Downtown/ Penn Quarter, Gallery Place, Mt. Vernon Triangle neighbors, who I gather are more walking types than driving types.
Metro-wise it appears the Mt. Vernon Sq metro station will be closed Monday the 21st. And I'm not sure if it is the map or what but the yellow line (according to the map-pdf) won't be wandering up to Fort Totten, terminating at Gallery Place. The other stations that will be closed are Archives and Smithsonian. Buses that normall travel through/near the Mall/Capitol zone will be limited with some lines terminating 1 mile to 1/2 a mile from the Mall (pdf map). Limited bus lines include the G8, the 90 buses, P6, and the 70 buses. It seems the 70 buses terminate at the Shaw Howard station.