I haven't seen the transcript so I don't know if he's being honest about being misquoted. On the other hand, being misquoted by the media is a pretty common experience.
If he did say that the U.S. didn't go to Iraq to install democracy, that's true. The U.S. did try to create a democracy there, but many have said that Islam and democracy cannot coexist. Maybe they're right. Look what democracy brought to Egypt...the Muslim Brotherhood. It took a military coup to get rid of the MB. I think the Middle East needs more military strongmen like al-Sisi of Egypt, to be honest. Democracy is overrated.
If you're asking me about Donald Rumsfield in general, it's hard to say. When he was Sec. of Defense his policies reflected President Bush's, just as Hillary and Kerry reflect President Obama's as Sec. of State. However, according to Michael Morell, the one thing that the USA blew in Iraq was the de-baathification policy. Rumsfield was in charge of that policy and he was wrong about it.