This morning I went to add a sound file to a forum, and when I clicked on the link button, it brought up just the "Link properties" box (just URL, Title, and Target). It used to bring up the Link properties and a File Browser so you could easily select files that were already uploaded to the course. I was running Moodle 1.3.2, so I updated to 1.3.3+, but it has the same result. Any ideas on what I did to take out the File Browser?
That's what students see ... were you logged in as a student?
No (although I've done that before) - I've tried it as Admin and as the local teacher, and neither one gives a file browser. I even tried the same thing on my test server (running Moodle 1.3.2) and it does the same thing (no file browser).
Ahhh. Got it. The format was changed. The File Browser comes up when you click on "Browse." Makes sense, it's just a different interface than 1.3.1. Sorry for the confusion. 
Yes, it's just meant to make it a lot easier to add a simple link when you already have it on the clipboard (which is usually the case).