um, Contra in the NES was easy. I used to beat that game without the cheat and less than 3 lives. had memorized every single thing on it

. now Contra: Shattered Soldier on PS2 was the hardest game i had ever played. eventually memorized the pattern and beat it with about 5 lives.
agree that NES G&G was near impossible to beat. Same with Super G&G on the SNES.
the trick to Ninja Gaiden's last boss came to.me in a dream. serious. you have to keep the swirl attack from beginning and get to boss with it. one or two hits and its dead. if you beat it and die on the 2nd boss form , the next time you come back, you start from the 2nd boss, and so on with the 3rd.