Slightly back to the red giant star thing, when a star exhausts it's supply of Hydrogen, it begins fusing helium. That requires a higher temperature, so the sun expands, but since it becomes so large, the outer shell turns red/orange (in any case, darker) due to the distance between it and the core, because the heat dissipates slightly before it reaches that far. In larger stars, after the Helium is all fused, it will switch to fusing Carbon, then Neon, then Oxygen, then Silicon, on down to Iron. Any elements heavier than that are produced by explosion of a supernova.
On a side note, no elements existed aside from hydrogen and helium in the early universe, aside from tiny trace amounts of Deuterium, Lithium, and Beryllium. Everything else has been fused together by a star sometime in the last 14-15 billion years.
For further information I would recommend looking up Stellar Nucleosynthesis. Also Big Bang Nucleosynthesis.
