I have seen that movie. ( Present Perfect, talking about experience)
I saw that movie last week. (Simple Past, usually with a time idea)
Yesterday I was teaching a new Imagine student M-san and we were thinking of examples of Present Perfect...
"I've lived in Sapporo for 15 years"..."I've eaten fugu"..."I've never met a famous person".
All of these are good examples and usually you can find them in text books.
But I laughed when finally M-san sat back in her seat, sighed and said:
"Ahh, I've learned this before. At school!"
It was a perfect use of the present perfect. :-)