Will the hotel open for walk-in take pictures during the Christmas Eve or Christmas day? Will the restaurant open too?

Yes it will

Yes

Yuppers

We were just there. I didn't see any signs saying anything was gong to be closed but I'd call to verify

Absolutely!

Yes, the hotel will be open, as for the restaurants I would call to ask about the particular one you want because more than likely if they are open it will only be for a limited number of hours.