Well, by "save the economy," I mostly mean that the payments system never failed. You could go to a teller window or an ATM and get cash, companies would still take checks to settle bills, you could still use your credit card at a restaurant, etc. There was a time there (when Bush the younger was saying, "This sucker could go down,") that it was not certain that the payment system would remain intact. "Save the economy" equals "We were not reduced to barter to obtain the necessities of life."

Or did you mean the crushing homeowners and subverting the rule of law part?

Basically, the mortgage industry had gotten quite slipshod about establishing the facts of mortgages (such as documenting that there actually was a mortgage on the property). So when they went to foreclose, they were basically just saying to the courts, "Trust us. We can't prove it, but this guy did borrow the money and he did secure the loan with this piece of property. He hasn't paid the money back, so we get to take the house." The courts largely just let all that slide and let millions of homes be foreclosed on despite the lack of proof.

And it was true that almost all those people really had taken out a mortgage and almost all of them really had failed to pay the money back, but it's still crappy for the courts to just say, "We believe the banks." And because of those crappy practices there were some egregious errors—homes taken when the mortgage had been paid off years before (or there had never even been a mortgage), because how could the courts tell the difference between a bank that's just been careless about documenting the facts and a bank that's actually wrong on the facts?