OO-concepts are pretty standard, since all CS progams include them. Review how these concepts specifically work in whatever language the job is for, since terminology and rules can vary. One of the best ways to prepare is to actually write some code. Try implementing a basic data structure, like a linked list or a queue. I've found this to be a useful refresher in some of the basic language concepts, and will help immensely if you are asked to write any code during the interview.
It may also be helpful to review your own attributes. Look through your resume and write down some points about each thing on it, in case you are asked. Think about answers to some of the basic questions: "what was a significant achievement you made?" "tell about a time you faced conflict" "where do you see yourself in 5 years?" Being ready for these questions will make you more confident and more attractive.
It's great if you know the answers to the technical interview questions, but if you don't:
- Tell the interviewer whatever part of the answer you can come up with
- Describe your thought process, to let him or her know that you aren't completely clueless, and give some demonstration of your problem-solving ability
- Tell him or her how you would find the complete answer/solution, and which resources you might utilize
Nobody has all the answers. You just need to prove that you are capable of finding solutions to things you don't already know.