I did not click on your link (I have no idea whether it is safe), so I don't know what it says. I recommend reading more than just one information source (as many as you can). Since anyone can post anything online it is risky to rely on just one not-so-well-known source.
If I go ahead with bankruptcy, will their house be blacklisted?
"Blacklisted" is not the right word, but I'll assume you meant "at risk." The house is safe if it belongs to your parents (not you), and your parents haven't cosigned any of the loans you can't repay. If your parents HAVE cosigned loans for you, come back on here and tell us (1) in which state your parents' home is located and (2) what, if anything, the cosigning documents they signed said about their house.
And how to improve our credit score post bankruptcy?
You started your post saying "I" this and "I" that. Do you really mean "our," and if so, who is included in that plural? Do your parents also need to declare bankruptcy, and if so, why?
One last bit of information: each state has laws that exempt certain assets of a debtor from being taken away by creditors even if the debtor does not declare bankruptcy. If you say in which state you are now a legal resident, people here (or you, if you're so inclined) can find out about your state's exemptions.