What sound is used for the keyboard in the song everything in its right place by radiohead?
It's a Prophet 5 synthesizer programmed to sound like an electric piano (a Rhodes), with lots of compression.
Was there ever a radiohead song used in a television commercial?
Yes, "No Surprises" from the album OK Computer was used in a commercial. It might have been a car commercial, but I can't recall.
Did Radiohead cover Something by the Beatles and if so what album is it on if any?
Radiohead did cover the Beatles' "Something". It is on the "Raretrax 2" album.