UnScramble this Word: c e l s e l m i?

Questions

what simon and garfunkel lp was britain's biggest-selling album of the '70s?

which band reached no 8 in 1985 with 'johnny come home'?

who realised a 1987 album called 'document'?

in what year were radiohead formed?

who realised 'things i've seen '?