Do you have other features turned on, that permit you to enter text? For example, can you post a new article, forum post, send an internal message or create a blog post?
As far as AJAX goes you probably want to turn off (at least for now) those features if they aren't already. You'll find some options on the Features admin pages, under the "Experimental" tab/section. You can turn off the WYSWYG editor here too, if it isn't already.