First off, two items/issues have been confirmed and replicated.
Issue #1: You did not select any valid comments
This is actually not an issue. You were seeing this message because the comments you were attempting to select had already been published. This is due to the fact that we had originally opted not to enable comment moderation in the vbulletin configuration.
I've enabled the global option in vbulletin that allows users to decide whether or not they wish to enable moderated blog comments. By default, this does not automatically enable commenting on each blog. Each blog has individual switches/options for this in the blog control panel.
Issue #2: Attempts to delete both blog entries and blog comments will redirect the user to seobook.com
Delete attempts initially direct admins/mods to http://www.netbuilders.org/blog_inlinemod.php?b=131. Please note b=131 is the post ID. This is the usual Soft Delete vs Physical Removal + Reason form. The form appears to begin processing the user input, then redirects to one of the NB advertiser URLs (i.e. seobook.com, parked.com).
On a side note, the same delete mechanism is used for forum posts, has been tested, and appears to work.
I have no idea where this is coming from. I don't have access to the server so I'm going to have to talk to Will about how NB advertiser files are served. One of the files may have replaced a blog file dependency.