After a full scan it found 4 wallets, 900 encryptet keys and 1800 unencrypted keys. It only imported those 306 keys from last time. 0 coins. Guess my coins are lost forever.

I made 4 or 5 backups back then. But I forgot about bitcoin for a while because of the low value, and one disk after another failed. I'm even pretty sure I made an online backup, but I can't find it anywhere...
Thanks for all the help though!
Contact
http://www.datagenetics.com/ and offer them a portion of the hoard if they manage to open it?
Since 'change' privkeys are generated based on a sequential seed iirc, you might be able to get into others other using those and a smaller amount of bruteforcing, if not they may be able to take the wallet apart and avoid the corrupted areas crashing bitcoin-qt. Worth an email at least eh?
I sent them a random one just to tell them about bitcoin the other day, they might be interested.
Check out their blog for some of their pretty amazing work, and some comedy including this.
