A photon is a particle with a wave inside. Photons of higher frequency are bigger than photons of lower frequency. All photons have the same energy. Intensity means that the amplitude of a photon is bigger. The Uncertainty Principle results from the limits of measuring devices.
Laser beams are always visible by themselves.
Sometimes you feel like a wave, sometimes you don't. There is only one correct model of the atom. Electrons in an atom orbit nuclei like planets orbit the sun. Electron clouds are pictures of orbits. The wave function describes the trajectory of a electron.