During the summer yes but in off season no. You need to check the Disney web site for the time you are going to see which nights there will be wishes.I think there is a list here on the DIS under park hours. also. I am currently waiting for Dec. which won't be posted till mid October As they are posting later and later.
Depends on when you go. During times of special activities (such as MNSSHP) they don't because the park closes early. Also during slow( or "value season") times it may only be done a few times per week.