I suggest
Perfume: The Story of a Murderer by Patrick Suskind. I read it a while back, but I really enjoyed it. It's not exactly a "Harry Potter" or a "Twilight", though.
If you're interested in something a bit denser but not ancient, you could go for something a bit more 19th century with
Frankenstein; or, the Modern Prometheus by Mary Shelley, or anything by Charles Dickins. As for 20th century literature, I recommend anything by Ernest Hemmingway, J.D. Salinger (he wrote other things aside from
The Catcher in the Rye), or Franz Kafka... A pretty random selection of three authors, but I could go on an on about each writer's unique style. If you're not really that big on books written before 1980 (teehee

), but if you're still interested in reading some, I suggest you start with Salinger, and then move on to Hemmingway. Kafka's works can be a bit... confusing.