recommendation from my pre-health adviser who was on the med school admissions committee for decades told me. just know the basics. for example, just know that it's goal is to provide universal coverage by requiring them to purchase a plan unless they already have one. of course you'll need to know more if the interviewer will ask more specific questions. however at temple, they didn't, and i don't think they will. remember not to take sides unless you are specifically asked whether or not you support the reform. if you want to more, simply google it or go here
http://www.healthcare.gov/law/index.html
In this case, your play on words is important. You should says something like "Well, from my understanding..." or "I don't know too much into the details but what I understand is...". You might not be able to say much, but if you throw your lack of knowledge out of the way with the initial statement, and proceed to supply information; its basically disguising the fact you don't know much. Does this make sense?
Example: If someone asks "How many bones are in the foot?"
"Well, I'm no expert, but I learned in my anatomy class that there is the calcaneus, cuboid, navicular, talus, metatarsals, and phalanges..."
This is completely different from saying
"In my anatomy class I learned about calcaneus, cuboid, navicular, talus, metatarsals, and phalanges, but I don't know that much."
Ending with the negative statement implies incompetence.