Try this to post pics:
Click "reply" like you are going to make a post.
Type some text or a period or something in the large white text box like you always do when making a post (you have to do this because your picture will not post unless something is typed in the regular text box).
Under the white box where you enter text you will see the words "Additional Options" in blue. Click those words.
Another smaller white box will appear w/"Attach" on the left and "Browse" on the right of it. Click the "Browse" button.
This should open a window to your pictures and documents and stuff on your computer.
You then go into that box and find and pick what you want to post by double-clicking on it.
Then press the "Post" button. Your picture should appear in the thread.
2 other things:
If a pic won't post, it may need to be resized. You can do that in your Paint function by pressing "Image" and "Stretch and Skew" and resizing it (if it needs to be resized, it's usually that it needs to be smaller).
Also, your pic needs to be a jpg or gif. You can also make it these in your Paint function.