Originally Posted by PatriceJ

There's no way I have discovered to delete a whole blog at once. We have to delete the entries. Once the entries are gone, it's as though the blog never existed.

To delete specific Entries, click the little checkbox to the right of the entry title.
To select all entries on a page, use the drop-down menu next to your blog's title called "Inline Mod", "select all ..."
Now go to the bottom of the post list. Use the drop-down "Moderation" to delete everything selected.

repeat the steps until everything you want deleted it gone.