We've done the World of Color first show. I haven't seen the new DCA entrance open yet, but we used to be able to walk toward the exit of DCA (would probably be in front of Carthay Theatre now) and catch the beginning of the fireworks in Disneyland. Standing at the right spot there or in Downtown Disney you get to see a good portion of the bigger fireworks which is usually pretty awesome.

Time you are going is a good time since the kids are usually back in school and its just before they start the Halloween theme. I haven't looked at a schedule, they sometimes take rides down then because its an in between time. Need to check the thread here on ride schedules, but Mansion has normally been converted over by 3rd week of Sept to Nightmare Before XMAS in recent years.