you're not doing anything wrong with the UBB code, it's the URL (address) you keep getting wrong...
that image you just posted had the URL:
http://clanjones.tripod.com/Oddworld.html/abe2.gif
what you must be doing is looking at the source of the page and pasting the 'relative' URL of the image onto the end of the URL of the page...
so...next time you try and post an image, right-click the image, select "Properties" then copy the URL that is shown somewhere on the dialog, then paste it into the UBB IMG tags...
...now you try...
[ November 8, 3001: Message edited by: Idiot Head! ]