Second interview- with human resources

I was on my first nursing interview for an LPN position with the director of nursing at a nursing home nearby. It went very well and I was called for my second interview with human resources for Wednesday morning. Does anyone have any advice as to what to expect with human resources?

I was asked to bring along 2 letters of recommendation. 1 letter is from my current employer the other letter is from a nursing instructor. The nursing school was closed today due to snow which delays the letter going through the mail and getting there by Wednesday. I am going to see if I can pick the letter up from the school tomorrow if they didn't already send it out. If they sent it out or can't give it to me, I was going to bring along a copy of my med-surg clinical evaluation that has a statement from my med-surg clinical instructor. Is that ok do you think?

Feedback, advice, interview questions greatly appreciated!