*Takes deep breath*
Fantasy: If you are looking for books with dragons, then i suggest The Enchanted forest Chronicles by Patricia C. Wrede. I know it sounds childish, but it's not. Also, i recomend The Fire Within by Chris D'Lacey. the third and fourth book get a little weird and sci-fi, but i love them anyway.
Not dealing with dragons, I enjoy the Rose of the Prophet trilogy by Tracy Hickman and Margaret Weis.
Sci-Fi: anything by Michael Crichton (RIP) or Douglas Preston and LIncoln Child. Note: these last to MUST be grouped together, the books they wrote individually are not nearly as good (in my opinion) as the joint novels. their books do not go in any particular order (other than the dance of death trilogy) but they all involve the same characters, so it is probably best to read them chronologically. and if you are into REALLY sci-fi stuff, then I like Pandora's Star by Peter F. Hamilton. we're talking space travel, aliens, the whole nine yards.
So yeah ... that's all, for now. chances are i will post with more books as I think of them. I read toooooooooo much