The moral of the story is: don't use freecreditreport.com. It's awful. According to the FTC (Federal Trade Commission) annualcreditreport.com is the one to use - it actually is free and not just a trick.
**Update** I called today and was able to cancel my account, and get a refund (though they say that it is not their policy to provide refunds). To their credit, the person on the phone was nice and reasonable and I spent very little time on hold. Not an excuse for the questionable methods of getting people signed up, but at least it wasn't as difficult to reverse as I thought it might be.