S.T. Coleridge is an interesting poetic figure. An opium addict who imaged an imaginary country called 'Xanadu', based on an Asian legend about one of the descendants of Genghis Khan, Coleridge's visions are very scattered and lacking in unity. His poems, while some soar to great heights, are often confusing or pedestrian, and in this regard he is a lesser poet than Blake or Milton.
Despite this and his constant dabblings in various religions and his unsystematic attempts to grasp a deep unity in the universe and in all knowledge in the realm of the spirit, along with some beautiful poems like the Ancient Mariner and some good essays and prose works (such as the Biographia) make Coleridge an essential part of any canon of English literature. He is a genius, even if not an outstanding one, and worth reading at least once.
The Oxford Collections are generally of very high standard and worth purchasing for every canonical author.