Saint Young Men since it's about Jesus and Buddha being bros. And my brother refuses to read it for some reason.

great romance:
- Toradora!  
- Kimagure Orange*Road
- Maison Ikkoku

great comedy:
- Lucky*Star
- SKET Dance
- Sexy Commando Gaiden - Sugoi yo! Masaru-san

great shoujo:
- Shoujo Kakumei Utena
- Garasu no Kamen (Glass Mask)

best shounen:
- HUNTERxHUNTER

best sports series:
- Inazuma Eleven
- Inazuma Eleven GO

best angst:
- Key the Metal Idol
- Ima, Soko ni iru Boku

Hajime no Ippo
Initial D
Gurrenn Lagan
Bamboo Blade
Midori Days
Sayonara Zetsubou Sensei
Welcome to the NHK
Shin-Chan
Chii's Sweet Home

Death Note - anime
K-ON! and K-ON!! - anime, if you like moe
Elfen Lied, only if you like bloody anime. Both anime and manga
The Melancholy of Haruhi Suzumiya - anime and/or visual novel
Steins Gate and Chaos Head if you like really vague anime's with all sorts of difficult theories.
Code Geass
I'll post more when I get back home ^^

Bump.

Bakemonogatari
Pandora Hearts
Soul Eater

Anime:

Gintama - Most hilarious anime you will ever watch... With some good fights aswell.
Full Metal Alchemist - Amazing story line.
Death Note
Desert Punk
Samurai Champloo
HunterXHunter
Tenjo Tenge

Manga

Naruto,Bleach, One Piece, Hitman Reborn, Toriko, Fairy Tail, BeelzeBub, Claymore, Hajime No Ippo, The Breaker/ The Breaker: New Waves, Veritas, Trace, Noblesse, Zippy Ziggy, Tower Of God


... All i can think of atm

Pokemon Adventures
Blade Of The Immortal
Vagabond
Slam Dunk
Toriko
HUNTERxHUNTER (Best shonen)
Fullmetal Alchemist