In order to do away with the objects with red sparkles around them you have to use dark magic. In order to use dark magic you need to use the Polyjuice Potion (or use an evil character on freeplay -- e.g. Lord Voldemort, Tom Riddle or Barty Crouch Jr.). Evil characters' Wingardium Leviosa spell is changed to the Crucio curse (but works just the same as Leviosa) and can now destroy the red sparkly objects.