Find an image you want (for this example, use the NSC logo at the top) and right click it. Select properties. Highlight the URL address in the box that pops up with the left mouse button, then right click and select copy. Close the box.
On the thread you want to post on, choose the 'post reply' button rather than the quick reply bit down the bottom. Above 'your reply', click on the little IMG box in the vB code section. Right click and select paste to copy the URL into the box that pops up. Click OK.
Choose 'preview reply' to make sure the image comes up first.
Voila!
You can use quick reply to do the same thing if you paste the URL directly into the 'your reply' section, then add the IMG tags at either end.