Dragonslayer
Characters
Galen Bradwarden - Galen is a chaos mage. He is studying to be a Wizard, but unpredictable magical effects surround him. Most of these are cut from the film, but his conjuration of a horse just by thinking about it at the end of the film is evidence of a strange magical talent. He might even be considered a Sorcerer 1/Wizard 1, with the addition of a level of Fighter by the end of the picture. Galen clearly knows the value of a reach weapon, and is proficient with medium armor, shields and simple weapons (spears, etc.) He apparently forgets to bring most, if not all, of his material components with him on the trip. High stats include Constitution, Charisma and Wisdom, but, sadly, not Intelligence.
Valerian - Valerian is a Rogue, probably a simple Rogue 1. She has put most of her skill points into Disguise (obviously, as she has fooled everyone into thinking she's a he.) She's got a high Wisdom and a powerful Will, but is not particularly Charismatic. Her clever creation of a sheild for Galen from Vermithrax's scales shows a high intelligence.
Ulrich - As a lich, Ulrich is very wily to leave his phylactery unhidden. He's clearly a very high level Wizard in life, but he knows Vermithrax is a force to be reckoned with. Thus, he casts an extremely powerful evocation (probably force-based) on his phylactery, triggered with him as the target when the phylactery is destroyed. At a minimum, I'd place Ulrich as a Wizard 20, as anyone who can cast a spell that will kill a dragon in one fell blow is at least near-epic level. High stats include Intelligence and Wisdom. Low stats include Strength. Non-stats include Constitution.
Tyrian - Tyrian is not a particularly high-level character, as evidenced by his inability to defeat Galen in a simple one-on-one contest. He talks tough, but Tyrian can't be better than Warrior 3 or so.
Princess Elspeth - Elspeth is an Aristocrat who fancies herself something more. She is clearly very well educated and painfully Lawful Good in alignment. Aristocrat 5 with a very high Charisma.
Vermithrax - The real star of the film, Vermithrax is a Red Dragon so ancient that his color has faded to a dull brown. His wits have faded a bit, too, and we can pretty safely assume that Vermithrax is rapidly approaching the end of his exceptionally-long draconic lifespan (take a look at those tattered wings--a draconic condition similar to male pattern baldness in humans.) Many have erroneously stated that Vermithrax is female, because of the presence of young within his lair, but this is incorrect, as the novelization of the film described the mating of Vermithrax with an unnamed female dragon who, showing the progressive nature of Dragon culture, left the young with him to raise. Probably not a great idea, as he is extremely negligent in this regard. Those who reject novelizations on principle are invited to explain why a female dragon wouldn't want virgin males instead of females as sacrifices.
Highlights and Gaffes
Dragonslayer is obviously fairly loose in its interpretation of the D&D rules, and this can be attributed to the general sloppiness of the whole adventure. The hallmark of a beginner DM is to skip straight to the really interesting creatures, regardless of the levels of your PCs. The deus ex machina ending, with an NPC Wizard/Lich coming to defeat the dragon for the PCs is also typical of an inexperienced Dungeon Master.
Of course, you can't blame the DM entirely. The party composition is pretty poor (possibly due to a low number of available players). The only cleric who even makes an appearance in the film is obviously an NPC, as no sane player would attempt to turn a Dragon!
Be that as it may, the DM does succeed in creating a rather interesting and exciting story. He can be forgiven partially because in 1981 D&D was still quite new for many people, and a lot of very young players picked up the game, excited by the premise but a bit too immature to fully absorb the complex rules.