I think it's a good idea for you to have your resume with you, in case they refer to 'oh, and two years ago'.... and *if* you draw a blank on what exactly they are referring to,(maybe it was a 2 month volunteering trip that you went on, that slips your mind) you'll have it in front of you. A pen and notebook to write down some notes when you ask them ?s might be a good idea, just don't be too focussed on writing things down that you lose track of what they are saying. They will probably ask you for your ID (if the admissions staff aren't already familiar with you) and it's never a bad idea to have a pen handy. If there is an essay portion, especially.
Good luck!!!!