Attaching pictures here is not like "the other" forum.
The mountain icon is used if the picture is already on a web-site somewhere else. If it is, you can go to that web-site, right click on the picture and select "properties" in the pop up menu.
In the window that opens, copy the address. It will look something like this: http://www.google.com/images/dogeatingachipmonk.jpg
Paste that address in the popup window you get when you click the mountian icon. The picture will display like in StefanJ's post.
If you are in the "quick reply" window, click on the "go advanced" button.
Scroll down to the additional options section and click the manage attachments button. In the popup window, click one of the "browse" buttons. Find the picture you want, click on it, then click on "open".
When you are done adding photos, click on the "upload" button. When it finishes, click on "close this window".
All you have to do now is click submit reply, and the pictures will show up at the bottom of your post.