I would recommend Wall St between College and York. The Law School is along here and the Sterling Memorial Library. The Hall of Graduate Studies is also there although it would be locked on a weekend. Another place is High st between chapel and Elm. You can access the old campus from here (it should be open as long as the university is open, which is most of the year) or you can walk down liberty walk between Branford and Jonathon Edwards Colleges. The Old campus has a variety of architecture, which could be nice. If you look the names of these places up you will be able to see them labelled on google maps.
Re: First Look in downtown New Haven/Yale area?
we got a little antsy/ silly toward the end. It took forever.