Suggestions: Good locations for student watching (always entertaining) include Norris University Center, the Lakefill (but maybe not in November/December, since it’ll be a bit cold), and the lobby of the Ford Building. If you want a bo$$ view of the lake/Evanston/Chicago, go to the top floor of the parking garage of the visitor center building. Also, if you like jogging at all (or taking very long walks), I suggest you go on a run along Sheridan from South Campus to North Campus, follow Sheridan to where it merges into Ridge, and then follow Ridge to the giant Bahai temple.
And yeah, sit in on a class in a subject you’re interested in. Have fun! 