In the interest of making as much of a one-stop-shop as possible apart from collectibles, I've compiled all 28 achievements that aren't related to the two big sets of collectibles into one video.
For Angel Goat and Boulder of Death, head over to the hill behind the red house and the folks having a bar-b-que at the start. Stand still for 5 minutes to unlock Angel Goat, then push the boulder down the hill to have it roll over the folks in the back yard to unlock Boulder of Death.
These achievements can be seen starting at the 00:57
mark in the video below.