When you hover over the pic you want in photobucket a drop down list should should show up.
Click once on the link that shows up with the [img] in it.
The link in there should now be highlited.
on the keyboard press CTRL and C keys at the same time. You just coppied the highlited link.
Now got to the window with your open FTE reply message.
Click in the text box where you want the picture to be.
on the keyboard again press CTRL and V keys at the same time. you just pasted the link.
you should now see the link in the FTE text box.

Hope that helps.