Deliberate mistake: Ash's car breaks out into the courtyard and the whirling, windmill thing batters the Deadites aside. We see the carnage a couple of times filmed from different angles, one Deadite, planted, legs apart, gets battered twice and the guys who come in from the left and are quickly jerked off screen are shown again seconds later.
Deliberate mistake: Rhododendrons, visible in the opening scene and mentioned specifically in the shooting script, do not grow in the Adirondacks.
Suggested correction: Several varieties of rhododendrons absolutely grow in the Adirondacks and are native to the region. Rhododendrons are native as far north as Nova Scotia.
Deliberate mistake: When Jafar sees Aladdin reflected in Jasmine's crown, Aladdin is the only thing visible. This isn't possible- we should have also seen the background of the room, the objects around him, etc.