I am going to have to guess, because you did not provide much information.
If all of the pictures with Spots are on pictures you took with a flash, it is most likely "dust circles".
If you use flash in a dusty environment, dust particles floating in the air just in front of the camera lens are illuminated by the flash.
This can result in different sized cloudy circles on any part of the photo.
If the pictures were taken in your home, it is possible you need to check the filter for your central heating/cooling system.
I saw a TV show about paranormal environments and they said the circles were caused by ghosts. Of course, their photos were taken (with flash) in a dusty old building.
But it is not ghosts, it is floating dust particles.
I use a Panasonic Lumix DMC-TZ1 camera. Up until recently, I was very pleased with the pictures but on a couple of occasions, opaque spots are appearing randomly on prints. Does anyone have ideas on why this is happening? Any input is appreciated - thanks!