Top Ten non-Star Trek novels in my mind right now, not neccessarily in order.....
(Note: Some of these are my favorite one book from a series of books but are not intended to stand apart from the series itself)
The Stand - Stephen King
Truly epic end of the world story.
A Storm of Swords - George R. R. Martin
So far, one of the best single epic fantasy novel's I've ever read.
(Game of Thrones is also excellent as is the Series in general........)
A FellowShip of the Ring - J.R.R. Tolkien
This one novel is my favorite of the series, but also represents the series as a whole being excellent.
The Gunslinger - Stephen King
Again, this book is intended to represent the entire series which as a whole is epic and awesome, even though the last couple books in the series were not as strong as the first 4.
Mercury Falls - Robert Kroese
A recent addition and one of the best books I've read in a long time! Those of you open to book recommendations should definitely be encouraged to give this book a spin if you haven't already!.
Harry Potter and the Goblet of Fire - J. K. Rowling
Another single book that represents an entire series of excellent books. This could have been my favorite as well as Half Blood Prince or Prisoner of Azkaban or even Goblet of Fire.
Foundation book 1 - Asimov - Most of the Foundation series was excellent but IMO, the first book was the best.
Ender's Game - Orson Scott Card - while I didn't care for the next 3 books in the series nearly as much, the first book was truly excellent.
Ready Player One - Ernest Cline Admittedly a personal favorite that is not as "well-written" as the rest of the books listed here and certainly won't go down as "classic Sci-Fi" for the ages.........however, it's been a while since I've had that much fun reading a book. (Until I got to Mercury Falls that is.....

)
Forbidden - Ted Dekker - Another book that I realize is more my own personal taste, but it's the first part of another trilogy from a Fantasy/Sci-Fi-ish type guy who has done so much so well. Like Ready Player One, it won't go down as a classic of literature, but I read it in about 1 sitting and thought it was pretty stinking good, especially as an introduction into a new series.
Honorable Mentions:
SlaughterHouse 5 - Vonnegut
The Moon is a Harsh Mistress - Heinlien
Duma Key, The Talisman/Black house, Four Past Midnight and countless other King books - King
The Hunger Games Trilogy
Priest's Graveyard, Circle Trilogy (Black/Red/White) (And about 10 other books that tie into that series) - Dekker
The Taking - Koontz (And about several other of Koontz's best......)
Small Gods - Pratchett