Henry Fielding: Tom Jones
Daniel Defoe: Moll Flanders
Both really good novels, and a fascinating glimpse into 18th-century Britain (so different in tone and feel to Dickens)
Vanity Fair
The Picture of Dorian Gray (gorgeous dialogue)
How about D H Lawrence? I enjoyed Sons and Lovers. Women in Love is meant to be his masterpiece, however.
Joseph Conrad: The Secret Agent
E. M. Forster: A Room with a View (the film is superb)
Aldous Huxley: Chrome Yellow (my favourite novel)
Evelyn Waugh: Brideshead Revisited
Virginia Woolf: To the Lighthouse
Graham Greene: The Heart of the Matter
Nabokov: Pale Fire
Ian McEwan: Atonement
Hilary Mantel: Wolf Hall
Kurt Vonnegut: Slaughterhouse 5
Edward St Aubyn: Melrose novels
Powell: A Dance to the Music of Time
I'm a huge fan of Anthony Burgess. Amazing novelist, and superb prose stylist. Try his Enderby books, or Earthly Powers (which should have won the Booker).
Harold Bloom compiled a list of the greatest books ever written, beginning with Homer and ending with writers like Cormac McCarthy and Jeanette Winterson. Take a look at that if you need ideas. It makes you realize just how many classics there are. I've never read a word of Henry James, Iris Murdoch, H G Wells, Ford Madox Ford, Don De Lilo, Martin Amis, Antony Trollope...oh, too many to name.