J, Don't worry about raw peanuts floating when you are boiling them. That is normal, and okay.
Some people like to place a plate inside the pot to push the peanuts under the water. In the end, it really doesn't matter.
Raw peanuts will absorb the water, and sink when they are ready.
Our motto at Boiled Peanut World is "Boiling softens the peanuts, soaking and simmering wets the peanuts, and infuses flavors."
After your boiled peanuts have softened to your liking, turn off the burner, and let the peanuts soak as the liquid cools. This cooling will allow the peanuts to absorb the water, and seasonings.