Interesting mix of "serious" literature and popular fiction. Some surprising omissions: Midnight's Children by Salman Rushdie (won the Booker's Booker -- may be over 25 years ago); Remains of the Day by K. Ishiguro; Atonement by Ian McEwan; The English Patient by Michael Ondatjee (book is much better than film). For what it is worth, I recommend these works highly. The New York Times recently did a similar survey of the greatest works of American fiction in the last 25 years; hard to argue with any of them, and the top three are bona fide classics:
Winner: Beloved, by Toni Morrison
Runners-Up:
Underworld, by Don DeLillo
Blood Meridian, by Cormac McCarthy
Rabbit Angstrom (Four Books), by John Updike
American Pastoral, by Philip Roth
Again, I strongly recommend all of them. These are definitely "American" novels, not merely because they are written by American authors and set in North America, but because each of them explore uniquely American events, attitudes and ways of life. That said, I would hope you don't have to be American to enjoy them. Note that McCarthy's recent novel, The Road, which I recommended in another string, recently won the Pulitzer Prize -- it is fantastic, and it is the sort of novel that readers of this BB might enjoy -- part science fiction, part horror story, part father-son drama. Very different from McCarthy's earlier works except for the fact that it explores "the evil that men do"

and is exceptionally well written.