Short answer, you can't restore the revision history from the information in the working copy - you can only create a new repository with the current wc state as the initial revision. Your best bet is to restore a backup of the repository.
This question probably fit better on Subversion's mailing list
us...@subversion.apache.org. Please including any details on how the repository is corrupted, including the output from `svnadmin verify C:\path\to\repository`. If the corruption is only affecting a certain part of the repository, you might be able to dump the unaffected part of the repository using `svnadmin dump` and restore at least part of the history.
Kind regards,
Daniel