I have no idea about any of those terms! It seems a lot more complicated in America! Here in general anything where the two legs are joined together at the crotch are tights and anything where the two legs are separate and need something to hold them up (suspenders or hold ups) are stockings.
The term pantyhose always makes my immature side laugh! You can get 'footless tights' here (the thick ones are practically leggings), but I don't think you could have footless stockings, they would just be leg warmers!