Perseverance, teamwork, and trying to do the right thing are ultimately rewarded, although some of Indy's methods are iffy. Standing up to bullies (in the form of the Nazi party) is a strong theme. Additional themes are courage and integrity.
Lots of hand-to-hand battles (fists, swords, whips) and plenty of guns, including one iconic point-blank shooting. Frightening/gross close-ups of melting faces and vengeful ghosts. A memorable scene of a man's head hitting a propeller -- blood splattering is shown. Indy is pursued by spear-wielding natives who want to kill him. Indy and Marion are lowered into a pit of poisonous snakes; there's also a close enounter with some very large spiders. A bar fire leads to a man's hand being badly burned/scarred. Near-constant peril.
Some kissing and flirting (Indy's female students, in particular are quite blatant about it). When Marion is held captive, she's forced to dress up for her captor so he can admire her (she changes behind a screen as he waits/watches). Later the dress is cropped quite short. Implied sex between Indy and Marion; he's shown shirtless and getting out of bed.
Language includes one "s--t," plus "goddamn," "hell," "bastard," "damn," and "oh my God."
Nothing in the movie, but there's plenty of Indy merchandise available.
Drinking, Drugs & Smoking
In a scene played for laughs, Marion wins a drinking contest by pounding down enough alcohol to kill the average person. Other scenes also show wine/spirits drinking, including one in which Marion pretends to get drunk.