Had I still been a naïve teenager obsessed with the mythos of ancient volcanic disasters, a movie like “Pompeii” would have provided one hell of a visual wet dream. Here is an ambitious production mounted in the tradition of old Hollywood epics, stretched beyond the scale of a mere screen, and hitched to that dependable staple of disaster films that seek to show us an array of grandiose visions that are both terrible and awe-inspiring. Unfortunately, time and experience often separates us from simpler pleasures, relegating our measurements of entertainment to comparisons of other, more sophisticated endeavors. A read-through of the premise immediately conjures up all those conventional comparisons: among other things, the story contains a main character obsessed with revenge while fighting for his own life in public arenas (“Gladiator”), ancient roman political intrigue (“Troy”) and a blossoming romance between young faces that are separated by class divides (“Titanic”), all set in the foreground of a catastrophe looming in the distance (any number of well-known blockbusters of the past thirty years). Take away all those call-backs, and what you are left with is basically a competent action picture that retreads to the safety of its formulas, primarily because it doesn’t have the desire, much less the thought, to pursue more challenging avenues.