No, I think both the Imperial March (atleast definatly the Imperial March
) and the Throne Room music would be a wrong choice.
May I suggest use the Leia Theme from ESB?
It would be great, and definatly emotional, walking down the isle to that master piece.
As for the Funeral, I agree, but I would also incorporate the part where Yoda dies in that music score. I think that small piece is very powerfull.