To fix this, can I just go into the database and delete the frows from the "Blocks" table, or set bIsActive = 0?
Or is there a way to rollback the a page from the dashboard?
just go to the sitemap.
Click on the page and select 'versions' from the drop down menu.
Simply check the version you want to revert to and click "approve".
you can now delete the corrupted page.
I would be willing to add the link from the sitemap to version controls to the version document.