I'd really love to live in Nirn (Elder Scrolls world), specifically in the Summerset Isles. A runner up would Cyrodiil during the height of the Third Empire, before the Oblivion Crisis.
Summerset is gorgeous, basically an eternal late spring but with a comfortable summer climate and ethereal architecture. Video can't do it justice, you kinda have to explore it yourself to really grasp how beautiful it is.
https://www.youtube.com/watch?v=3gJwzPRHjfE
