Typically a postdoc interview presentation is for giving the members of the group you are interviewing with an idea about:
- who you are
- what you know (education)
- what have you done before, in terms research experience
- how you work
I have had presentations varying from 45 min lunch seminars that went over an hour with questions, down to 20 min presentation followed by 1-on-1s with the group members.
I have never heard of a 5 min presentation for an interview and I would generally say it's way too short to be meaningful. But that's besides the point...
I wouldn't worry much about showing any data, or complicated figures that will take too long to explain. It really does take longer than you'd imagine. Keep it to a maximum of 7-8 slides, and keep them very roomy... Don't cram too much into the slides, and don't try to say too many things. Any details they might be interested in will come afterwards in terms of questions. Oh and I would recommend starting with a meta-statement, saying something like "For this presentation, I have skipped all hard data and complex figures, due to time restrictions. But I would be happy to answer your questions about the nitty-gritty details afterwards"
A 5 min presentation will ultimately be more like an elevator pitch than a scientific presentation. A verbal cover letter, if you will. Focus on the reasons that made you apply for this position, and the parallels between your previous research and this position. What gave you the impression/confidence that you can do what they will ask you to do. If you can answer that question in 5 minutes I think you have done a good job.
Best of luck in any case :)