Dead Alive (1992)
In my opinion, one of the best blood and guts film there is! This story of a zombie virus perpetuated by a Sumatran "Rat Monkey" is a far cry from the types of movies Peter Jackson has become known for today.
Grindhouse: Planet Terror (2007)
Quentin Tarantino and Robert Rodriguez' film about a governmental bio-nerve gas that turns everyone into digusting sore-covered zombies. The death sequences are cleverly good and an absolute gore-fest from start to finish.
The Texas Chainsaw Massacre (1974)
A story about a group of teens who come across a family of psychos who have a knack for making BBQ out of their unfortunate victims. One of the first movies to inspire the series of masked slasher films that followed. It's a very gruesome film that highlights the evils mankind is capable of. Director Tobe Hooper noted Ed Gein as the film's inspiration.
The Devil's Rejects (2004)
Rob Zombie's follow-up to House of 1000 Corpses. The movie features the deranged Firefly family who get their kicks through making others suffer. After killing an officer, his brother will stop at nothing to exact his revenge and bring their killing spree to an end.
City of the Dead (1980)
Directed by Lucio Fulci, City of the Dead takes place in a small New England town where a priest has committed suicide in a local cemetery. His death subsequently causes the gates of hell to open, allowing the dead to walk the earth. Some of the death scenes are almost comical, but there is plenty of guts and gore.