My ancestors didn't own slaves, that I'm aware of, maybe if you go back far enough you'll find one that did, but I bet my ancestors got enslaved more often than they enslaved. I'm not stupid though. I totally notice the advantages that all that slavery we used to do affords me today.
I mean, my grandfather worked in a coalmine and he made like twice as much as the black guys he worked with...I guess discrimination was okay back then, you know, we used to pay African-Americans nothing and buy and sell them so...the transition took (is taking) a while to even things out!
Lebron James might own the Lakers instead of just play for them if it wasn't for slavery....who knows. He's got tons of money so he probably wouldn't accept your money if you offered, or maybe he'd donate to some worthy cause....but I think it would be nice to offer, or at least apologize on behalf of your ancestors or dead slave-owners in general.
Just to be "decent". No harm in that, right?