VegasBaby,
Just forget about suing them. You’ll just end up wasting your money as you have no valid cause of action.
With regard to 1, I have two basic questions: 1) did something funky happen in 2007. I believe Zillow’s just pulls public records. If Zillow’s lists it as sold in 2007 and it didn’t sell, I’d take a drive down to the county records office and make certain your title is clean. 2) If it turns out to be just a computer error, then why worry about it.
With regard to 2, I have to question why you really care. If your house isn’t for sale, then there is no listing agent for buyers to get in touch with and it just makes Zillows look bad. You also presumably don’t have a For Sale sign in front of your house nor a lock box, so people aren’t going to be stopping by to tour the house. Regardless, there is nothing illegal about them making this mistake. And, it hurts you in no tangible way.
So relax, have a beer, and watch the Ducks try and retain the Cup.