Süsü** a sárkány (Süsü the dragon) is a puppet-musical show (yup) and also a beloved series of children's books by Csukás István. The original series had 9 episodes and aired in 1977, while the sequel (Süsüke a sárkánygyerek / Little Süsü the Dragonchild) aired its 13 episodes in 2001.
* Dragons in Hungarian folklore usually have multiple heads (most commonly 7, or sometimes 3, 9, 11, etc.)
** "süsü" is also a word applied to people who are a little bit slow or simple, which Süsü certainly is
Üdvözöllek dicső lovag,
Szép a ruhád, szép a lovad!
Noble knight, you I greet,
Your garb is grand and so is your steed!
Szép vagy mint a rózsaszál, ó, te kedves királylány!
You are beautiful like a rose, oh, dear Princess!
(These are things most people can still quote)
Except, well, people are still terrified of Süsü, the fight doesn't go very well, the Princess throws a hissy fit, and eventually everything comes to light: The Dragon is not evil, the Princess marries the Prince, and people decide to allow Süsü to live among them anyway.
Here is the intro of the show (summarizing Süsü's journey), one of the most beloved sing-alongs of Hungarian kids in my generation. I still know all the words to it...
(Episodes are also available here, but only in Hungarian)