WordPress keeps removing paragraph tags

For some reason, my wordpress keeps removing p and br tags from pages or posts. Even when I copy in a piece of code with br tags in it, once I save and re-edit it, the tags go away.

This is really annoying, because sometimes when I insert an image, I want the new paragraph to start below it, but instead it starts half to the side. A good example of this is

http://www.gearfire.net/subscribe/

Any ideas? I tried disabling rich text editor, and made sure my XHTML setting was off, but to no avail.