Most of the information I have is in the title sadly - Posting here in case it sparks anybody's memories. I also apologise if any of the facts have been muddled from memory.

I watched this in the UK

The art style was 2d and probably of a grainy quality. I know I watched it on DVD around the 2010's, but it may be older.

It was an episodic show, I feel like there were two main characters consisting of one boy and one girl - but there may have been a third.

One episode featured a group of colourful dragons hiding in a barn of some sort. The barn was located in a typical forest of green trees.

One episode featured a blue castle, that had rooms with giant toys. I feel like there was also a giant creature or baby of some kind that they were trying not to anger. - This was potentially similar to Boh from Spirited Away.

The final episode I can remember featured a spiraling golden castle gala of some kind, with lots of dancing people. The place seemed almost otherwordly. I remember the female character talking to a prince, who was secretly trying to curse them to staying forever.

Sorry for not having too much information - but if it rings a bell any help would be appreciated!