I'd review my performance stuff. Namely what's V1 etc. What constitutes a wet runway, contaminated runway etc.
Also, review the practical IR stuff, ie approach ban, minimas, alternate requirements etc. Brush up on met decodes too.
Review CRM and think of practical examples.
Know the target company's fleet and routes. (ok, you won't know specific info but eg, if going for easyJet, I'd know that the 737-700s are being phased out for the Airbus 319 and they've recently aquired GB Airways with X routes from Y airport(s)) Knowing who key personnel are and the stock price (if relevant) is wise too.
You will be expected to have a reasonable practical day to day knowledge of the last type you flew as well.