It's nice that we have the ability to edit a post. We also need the ability to edit that post if we put up the wrong pic and want another one - or just delete the original altogether.
You can delete images. You have to click 'Edit Post', then go 'Advanced' and then select the 'Manage Attachments' option. The image when you hover over it has an 'x' in the upper right hand corner and clicking on that will delete the attachment. It's not easy though. I've never liked vbulletin's image attachment software.