Me

We would probably just laugh at the ceiling for hours

Probably Gandalf. I'd just ask him about all of his travels and in turn try to explain our world.

Tobias from Animorphs would be interesting.  I wouldn't mind just talking with him about things.  Emotionally, we come from fairly similar places.

24601

all of the teletubbies

I would hide in a closet all day

Yuki Nagato. I'd ask her all about space and alien life, and then we'd probably just hang out and read books or something. Like, not really interacting, but just separately doing our own things.