Busted Header Gasket ?'s. Also, easiest way to change headers?

Well, I got the header loose and took the old gasket off, just as everyone suspected, it was completely busted where the bolts had backed out.

So I get the new gasket, slip it on, get the header back on, start her up and.... STILL A DAMN LEAK. Shut it down, retightened the bolts, and still had the leak.

So all of a sudden I look down at the other gasket that came with the one I put on, and see that it is oval port and the headers I have are rectangle. Would this be causing the noise, or is the header possibly warped or bent? I bottomed out the H-pipe (hanging low, didnt have any hangers on it) on a friends driveway pulling in a couple weeks ago, and while the leak didnt happen right after that, it did a few days later. Could that have bent the header flange?

Also, what would the easiest way step by step be to change the headers assuming this is what I need to do?

Well, the exhaust was not on hangers, so thats why I was wondering if that might have changed anything. I've been led to believe that the headers are banged up, so I may perhaps just go ahead and get the correct gaskets first before I go and blow 200 bucks on new headers.