Freitag - as your friend, let me warn you:
Most of the movies posted here are, well, very <individual> tastes. I would suggest these three as starters:
Back to the Future: Childish, but a work of near comic genius by the ensemble.
Princess Bride: Best film exposition of the classic story form ever. Funny and touching.
Big Trouble in Little China: A classic depiction of the ugly American anti-hero.
And given your tastes - never, ever watch Hellraiser. Ever.
Arbiter Warrant