Applying for my own job?

HELP. Due to cut backs and restructuring, I have to apply for what in effect is my own job. I have been a trainer in IT for the past 10 years and have to apply for my own job. I will be expected to give a presentation, to three people who know me very well, on any relevant subject. The difficulty is what subject to choose. I have never delivered a presentation before and although it is not a good idea feel as if it should be on jumping through hoops. Please HELP.