I am now 44 years old and I seen this back in the early 70's I believe, it was my first horror flick and all I remember is a fully nude female hung upside down and split from naval to throat and bleeding out.

The second one was also in the 70's maybe early 80's and there are 5 or so young collage girls that get stranded from the car not working and they walk to a house that is creepy, the two old people and their son invite them to stay and one by one the girls are killed, and then there is a dinner scene where the girls rave over how good the food is only to find out that they are eating their friends, the closing scene is the son taking a silver serving tray outside and lifting the lid showing the two heads of his mother and father and the heads open their eyes and say the end. Cheesy but funny, not bad gore.

The first one could be Cannibal holocaust?

Watched the movie and it was not what I remember