The “Block Robots/Spiders” option enters HTML <meta> tags into your journal’s code to indicate that the content should not be archived or cached. Unfortunately, data feeds such as your journal’s RSS feed do not have similar tags that instruct spiders not to archive the data. As such, the feature in question has no bearing on other sites’ ability to read your RSS feed.

While it is not possible to entirely disable your RSS feed, you can limit its output strictly to the subject lines of your entries. To do this, you can go to http://www.livejournal.com/admin/console and execute the following command:

    set synlevel title

Your syndicated feed will only display public entries to logged-out users, along with anyone not on your Friends list. If your protected content has been archived on Google’s Blog Search, then it was archived at a time when the entry was public. Unfortunately, there is no way for LiveJournal to require the removal of the material in question; you, as the content owner, will need to speak with Google about this matter. You may also wish to consult legal counsel if you believe your copyrighted material has been archived without your consent, to discuss what recourse you have in this situation.