From the string of articles from technet, I notice one definite repair you seem to have not yet done, one that uses eseutil. You have tried the /r switch, but that will only perform a soft recovery, and my guess is that you are past that point. Try this:
1. Make sure that the system attendant, and directory service are started.
2. From a command prompt, type eseutil /p /ispriv
3. Click Yes to the warning that a repair should only be attempted if necessary (do you call this necessary???) The utility will do a "hard recovery" of the database.
4. BEFORE ATTEMPTING TO START THE IS, delete the log files as per the message that is displayed on completion of the utility. The logs you must delete are in the \exchsrvr\mdbdata directory, make sure all extensions are visible and delete all 3(?) files with a .log extension.
5. Try to start the store. If error message 1011 is returned, run isinteg -patch from the \exchsrvr\bin directory and then start the store.
Hope this does it for you. If not, let me know.
Ian