Fred gets a pretty good one, when he jousts against the Black Knight... on a motorcycle. To the tune of Bon Jovi's Dead or Alive. That is all.
Daphne took on the Black Knight earlier in the movie - and nearly got killed for her efforts (despite putting up a damn good fight)... and is saved by *Velma*, of all people, who boots the Black Knight square in his toodles.
The tar monster has just succeeded in trapping the gang (minus Scooby), and is suffocating them. Scooby (who has the control panel that can stop the monsters) backs away whimpering, glancing in fear at each Mystery Inc. member, while other monsters close in on him. Upon seeing this, the evil masked figure begins to taunt him. Big mistake - Scooby realizes that he's strong enough on his own, and saves the day by freezing the monster with a fire extinguisher. Then there's this little gem...
Masked Figure: (as Scooby is wreaking havoc on the assorted monsters) No! You can't do this to me! Who do you think you are!?
Scooby: Scooby. Dooby. DOO!(Smiles and slams the control panel onto the machine, destroying the monsters)
Scooby as Einstein by means of a magical potion (mixed with a helping dose of CMOF). Plus being voiced by J.P. Manoux.