Go to your photobucket page. There will be three URLs under the photo thumbnail.
Click on the third one (IMG Code.) It will automatically copy it for you. Post it into your Pet Talk post, and voila! You should have an image in your post.

Just be sure your photo is resized before posting, as it may be a large photo originally. You can do this on Photobucket as well by clicking "edit" above the photo thumbnail, and then resize. Choose website/email.