Final answer:
The statement regarding a patient's family members having high blood pressure should be documented in the Family History section of the EMR, as it relates to potential genetic health risks.
Step-by-step explanation:
The appropriate section of the Electronic Medical Record (EMR) to document the statement "my grandfather had high blood pressure, and my father has been on high blood pressure medication for years, but I've never been diagnosed" is in the Family History section. This section is specifically meant for information about health conditions prevailing in the patient's family, which can have genetic implications for the patient's health. Information such as family members with hypertension falls squarely into this category.