The first day you'll definitely be asked the basic questions. These are things like: "What did you do during the summer?" "Why did you choose this college/university?" "Why did you choose to rush?" "What types of things do you do for fun?" Etc.
Oh, and don't be afraid to ask THEM questions as well! I know I love being asked questions. You could always ask about pledging activities and why they chose to join their sorority. Be creative!