Greatest? Probably Raiders of the Lost Ark. A pitch-perfect introduction to the character,
Favourite though? That one is easy: Blade, arguably the movie that kick-started the modern comic-book era. It immediately sets the scenario of the vampires being these cool, underground kids and what is cooler in 1997 than an underground rave?
We follow an innocent human who thinks he’s scored a hot chick and the camera flashes to some important characters: the villain. His henchman. The human starts to realise things are not cool when he sees the gnarly soft core kinky things the vampires are into before the techno soundtrack (Confusion by New Order) reaches a crescendo and it starts raining blood from the ceilings. The kinky S&M vampires start covering themselves in it in a sexual fashion whilst the human character tries to crawl away. Beaten, he eventually arrives at the feet of Wesley Snipes titular character. The music kicks back in, the Vampires attack and we see Blade kid their asses with that cool disintegration effect when he slams them with silver.
Fantastic.