The scene in the library with the gang gathered around Velma reading is similar to a scene from Scooby Doo, Where Are You! (1969) that appeared in the opening credits.
The film was originally titled Scooby-Doo in King Arthur's Court after the [Mark Twain novel A Connecticut Yankee in King Arthur's Court, but was retitled The Sword and the Scoob after the T.H. White novel The Sword in the Stone.
During the tournament a man is offering peanuts. This is a reference to Fezzik's line in The Princess Bride (1987).
This is the last Scooby Doo! production give special credit to franchise creators Joe Ruby and Ken Spears, who both died months before it was released.
The food mentioned by Shaggy including fish and chips, bangers and mash, toad in the hole, Welsh rarebit, bubble and squeak, jellied eels, and angels on horseback are all actual popular British dishes. Fish and chips are fried fish and French fries. Bangers and mash are sausage and mashed potatoes. Toad in the hole is sausage cooked in Yorkshire pudding with onion gravy. Welsh rarebit is toast covered in a cheesy sauce. Bubble and squeak is a mixture of potatoes and cabbage. Jellied eels are boiled eels served cold. Angels on horseback are oysters wrapped in bacon.