I don't know of a movie but the POH (Section 4. Normal Procedures - Checklist Procedures - Preflight Inspection) details what you need to do.
On top of this look for missing screws, loose things (aerials, inspection covers, lights, etc), distortions in the panels and wings, control surfaces, IMPORTANT: balance weights on ailerons!, leaks from brakepipes, fuel caps secure after fuel checks, cracks in windscreen, tyre inflation, front strut inflation, etc. If you're near to Norfolk you are quite welcome to pop over and I'll take you through it all, but you probably aren't. I'm sure other 172 pilots on here would help you out if you are nearer to them.