Couch in a castle.

WYR have astronomy lessons on a tower or garden with moles?

Astronamy on a tower!!!! 😀 😀

WYR be a beaver or a faun? 😀

A beaver. ^.^

WYR have been in Charn or in Narnia to see a red/dying sun?

Charn. I'd be far less sad about it.

WYR learn Ramandu's song or the Great Snow Dance?

Ramandu's song. 😀

WYR try to enter and explore a seemingly mysterious empty house or wander around a mansion filled with antiques and many strange rooms?

Mansion, so long as I'm allowed to actually touch stuff. 😀

WYR have a prince you don't know propose to you or slip out of the city of a prince with an obsession for you?

The prince with the proposal because I could just decline.

WYR look at the sea from Cair or from atop Fledge while he is flying?

Ohhhhhh! Both! Bothbothboth! I love flying, but I love the sea too!

WYR climb the highest tower in Cair Paravel, or climb the tallest mast on the Dawn Treader?

Tower. Less chance of falling. 😀

WYR visit the Seven Isles or the Lone Islands?

Lone Islands. It's still Narnian territory.
WYR check out the sea-people's kingdom or visit Ramandu's Island?

Visit Ramandu's Island, I'm not sure of underwater kingdoms....

WYR take part in the Narnian summer or winter festivities?

Winter.
WYR play chess against Reep or against Lucy?

Hmmm... after much deliberation, I think It would be best if My opponent was reep, mainly because it was said in the Narnian books that reep sometimes made decisions based on what he would have done if he was really in battle,causing him to sometimes make mistakes that would have otherwise gained him victory in real life. 😀

Um...WRR Live in a wigwam or a hollowed-out tree? 😉

(I think I'd say the same, Ed. Plus with Reep, I could learn real-life battle strategies. 😆 )

Hollowed-out tree sounds cool.

WYR be in Anvard during Rabadash's attack or with Tirian at the tower?

Anvard.

WYR meet Trumpkin or Poggin?