Common Sense Note
Parents need to know that this was the first Star Trek movie to Go Where No Star Trek Flick Had Gone Before, to a PG-13 rating. It has some pretty gruesome violence and a macabre threat in the menacing Borg, a zombie-like, infectious, cybernetic race who could give younger viewers nightmares. Humans and Borg alike die in battles, with some limbs severed, and a Borg commander can detach her head at will. There is some generalized dialog about sexuality, as well as mild swearing. A historical Starfleet hero is revealed as a misfit drunkard; while his alcoholism is perhaps meant as pathos, it comes across as mainly comical.
Sexual
Content
Dialog about sexuality in general terms, mostly with the android Data being tempted by an inhuman villainess. He talks about being anatomically correct and programmed in "techniques." A human character described as a drunken womanizer.
Violence
Spaceship explosions, ray-gun fire, dead bodies seen. Grisly close-combat with the Borg, including snapped necks, injections-implants piercing skin, disembodied or hacked-off body parts, and dissolving flesh.
Language
More bathroom talk than usual Starfleet regulations, including "bulls--t," "hell."
Social
Behavior
Starfleet is notably racially, gender, and species-integrated (with the addition of Mr. Data, even machine-integrated), and there is a strong sense of friendship, duty, loyalty and, if necessary, sacrifice. Picard's vengeful attitude towards the Borg is called into question by a civilian, and he relents. Mr. Data puts his own wishes to be human aside for the greater good.
Consumerism
Tie-ins with three Star Trek TV shows, innumerable action-figure/book/video game spin-offs. Zephraim Cochrane forces the crew to listen to classic rock.
Drugs / Tobacco /
Alcohol
Quite a lot of drinking and drunkenness among the people of Earth, played comically.