suggest me a smart and deep anime\manga...

[Paragon Fury]

Sekirei.

Sure, you'll think its just about the T&A at first, then one day you'll be getting yourself a turkey sandwich from the fridge and it'll hit you like a bus that some serious business be going on there.

 

[Ultress]

First off anything Yasuhiro Yoshiura directs: http://myanimelist.net/people/6072/Yasuhiro_Yoshiura. The most accessible being Eve No Jikan,a 6 episode ONA series about human android relationships.

Haibane Renmei is also pretty good with tons of different interpretations and wonderful atmosphere in a relatively simple story.

As others have said Monster is labyrinthine in its plot and characters,though it can be slow at times.

Also while it is a comedy Sayonara Zetsubo Sensei is a scathing parody of society. Usually by taking concepts to the extreme and playing with anime tropes.

 

[Fishehh]

I would suggest Neon Genesis Evangelion

Spoiler: Neon Genesis Evangelion Information

In the year 2015, half of the human race is dead, and the survivors face extinction at the hands of giant biotechnology experiments called Angels.

Within the headquarters of the secretive organization called NERV, a special United Nations agency located in Tokyo-3, a handful of teenagers are trained to pilot the colossal super-entities known as Evangelions and battle the Angels on their own terms... whatever the cost to their minds and souls.

Shinji Ikari, whose father heads the NERV team that developed and maintains the Evangelions, is thrust into a maelstrom of battles and events that he does not understand. He is forced to plumb the depths of himself for the courage and strength to not only fight, but to survive...

Spoiler: Slight Neon Genesis Ending Spoiler

The ending is confusing and is almost impossible to understand, but the movies fixed it

GOSICK is also really good

Spoiler: GOSICK Information

Gosick is an anime that takes place in 1924 in a small, French-speaking fictional European country of Sauville. The anime centers on Kazuya Kujo, the third son of a Japanese soldier, transfered St. Marguerite Academy, where legends and superstitions are taken seriously. There he meets Victorique, a mysterious, brilliant girl who never comes to class and spends her days reading the entire content of the library or solving mysteries that even detectives can?t solve. The anime focuses on Kazuya and Victorique getting involved in different mystery cases and their struggle to solve them, at the same time forming important bonds with different people.

Code Geass is also very interesting

Spoiler: Code Geass information

The series is set in an alternative present, where the world is split by three superpowers, the Holy Britannian Empire (神聖ブリタニア帝国, Shinsei Buritania Teikoku?), the Chinese Federation (中華連邦, Chūka Renpō?), and the Euro Universe (ユーロ・ユニバース, Yūro Yunibāsu?) (with the exception of an independent Australia). The story takes place after the Holy Britannian Empire's conquest on Japan in August 10, 2010 a.t.b., by means of Britannia's newest weapon, the "Armored Autonomous Knight", or Knightmare Frame. In turn, Britannia effectively strips Japan and its citizens of all rights and freedoms, and renames the country Area 11. (Wikipedia has odd writers)

 

[Gigano]

I'd recommend these as more or less fitting the bill:
Grave of the Fireflies [http://www.themanime.org/viewreview.php?id=110]

I've been planning on watching it as I've heard great things about it. Is it better to watch subbed or dubbed?
...

Definitely subbed. The dubbing is pretty mediocre, and since it takes place in rural Japan, the Japanese voice acting is more appropriate for its setting anyway.

 

[eggy32]

I'd recommend these as more or less fitting the bill:
Grave of the Fireflies [http://www.themanime.org/viewreview.php?id=110]

I've been planning on watching it as I've heard great things about it. Is it better to watch subbed or dubbed?
...

Definitely subbed. The dubbing is pretty mediocre, and since it takes place in rural Japan, the Japanese voice acting is more appropriate for its setting anyway.

Good stuff. I watched it not long after you recommended it. I watched the subbed version. It was really good.